feat: §5.2 batch — trend lineare, soglia allarme, guide misure, daily check-in

Quattro feature del PRD §5.2 Tracking peso e progressi.

§5.2.1 Trend regressione lineare + proiezione
- @ketopath/shared/tracking/weight-trend: linearWeightTrend() (least squares),
  projectGoalDate() con cap a 52 settimane e check di direzione coerente
- 9 unit test (slope/intercept, segno, cap)
- /tracking: terza statistica "Trend settimanale" + frase
  "Al ritmo attuale raggiungerai 75.0 kg il 24 luglio 2026"

§5.2.2 Soglia di allarme peso personalizzabile
- Profile.alertWeightKg @encrypted
- profileInputSchema accetta il campo, profile.routes lo persiste
- ProfileForm: nuovo input "Soglia di allarme peso (kg)"
- /tracking: banner pomodoro "Sei sopra la soglia" con suggerimento
  "settimana di riparazione" senza colpa

§5.2.3 Linee guida "come misurare bene"
- Disclosure inline in WeightEntryForm con istruzioni tecniche per
  girovita, fianchi, coscia, braccio + tip generale (ora del giorno,
  metro morbido, stessa procedura)

§5.2.4 Daily check-in indicatori soggettivi
- Nuovo modello DailyCheckIn (date, energy, sleep, hunger, mood, notes)
  con unique(userId, date) e migration
- shared dailyCheckInInputSchema (zod)
- API: GET /me/check-ins (last 30), GET /me/check-ins/today,
  POST /me/check-ins (upsert sul giorno)
- /tracking: card lampo in cima con 4 slider 1-10 + Salva/Aggiorna,
  10 secondi di compilazione

i18n: namespace Tracking esteso (weeklyTrend, projection, alertEyebrow/Message/Hint,
measurementsHelpToggle + measurementGuides{}, checkIn*, mood). Profile esteso
(alertWeightKg + hint).

Schema migrations: add_alert_weight_kg, add_daily_check_in.

81/81 unit test verdi (9 nuovi). Lint, typecheck verdi.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/web/src/app/[locale]/profile/profile-form.tsx

@@ -66,6 +66,7 @@ export function ProfileForm({
               ? { targetWeeklyLossKg: initial.targetWeeklyLossKg }
               : {}),
             ...(initial.dietHistory ? { dietHistory: initial.dietHistory } : {}),
+            ...(initial.alertWeightKg != null ? { alertWeightKg: initial.alertWeightKg } : {}),
           },
         }
       : {}),
@@ -259,6 +260,31 @@ export function ProfileForm({
             )}
           />
 
+          <FormField
+            control={form.control}
+            name="alertWeightKg"
+            render={({ field }) => (
+              <FormItem className="space-y-3">
+                <FormLabel>{t('alertWeightKg')}</FormLabel>
+                <FormControl>
+                  <Input
+                    type="number"
+                    step="0.1"
+                    min={35}
+                    max={300}
+                    inputMode="decimal"
+                    {...field}
+                    value={(field.value as number | undefined) ?? ''}
+                  />
+                </FormControl>
+                <p className="font-display text-ink-soft text-sm italic leading-snug">
+                  {t('alertWeightKgHint')}
+                </p>
+                <FormMessage />
+              </FormItem>
+            )}
+          />
+
           <FormField
             control={form.control}
             name="dietHistory"

apps/web/src/app/[locale]/tracking/actions.ts

@@ -61,3 +61,47 @@ export async function saveWeightEntry(input: WeightEntryInput): Promise<SaveResu
   revalidatePath('/tracking');
   return { ok: true };
 }
+
+export interface DailyCheckInRow {
+  id: string;
+  date: string;
+  energy: number | null;
+  sleep: number | null;
+  hunger: number | null;
+  mood: number | null;
+  notes: string | null;
+}
+
+export async function fetchTodayCheckIn(): Promise<DailyCheckInRow | null> {
+  const res = await fetch(`${API_URL}/me/check-ins/today`, {
+    headers: { cookie: cookieHeader() },
+    cache: 'no-store',
+  });
+  if (!res.ok) return null;
+  const data = (await res.json()) as { item: DailyCheckInRow | null };
+  return data.item;
+}
+
+export interface CheckInInput {
+  energy?: number;
+  sleep?: number;
+  hunger?: number;
+  mood?: number;
+  notes?: string;
+}
+
+export async function saveTodayCheckIn(
+  input: CheckInInput,
+): Promise<{ ok: true } | { ok: false; error: string }> {
+  const today = new Date();
+  today.setHours(0, 0, 0, 0);
+  const res = await fetch(`${API_URL}/me/check-ins`, {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json', cookie: cookieHeader() },
+    body: JSON.stringify({ ...input, date: today.toISOString() }),
+    cache: 'no-store',
+  });
+  if (!res.ok) return { ok: false, error: `api_error_${res.status}` };
+  revalidatePath('/tracking');
+  return { ok: true };
+}

apps/web/src/app/[locale]/tracking/daily-check-in.tsx

@@ -0,0 +1,89 @@
+'use client';
+
+import { useTranslations } from 'next-intl';
+import { useState, useTransition } from 'react';
+
+import { Button } from '@/components/ui/button';
+
+import { saveTodayCheckIn, type DailyCheckInRow } from './actions';
+
+export function DailyCheckIn({ initial }: { initial: DailyCheckInRow | null }) {
+  const t = useTranslations('Tracking');
+  const [energy, setEnergy] = useState<number>(initial?.energy ?? 5);
+  const [sleep, setSleep] = useState<number>(initial?.sleep ?? 5);
+  const [hunger, setHunger] = useState<number>(initial?.hunger ?? 5);
+  const [mood, setMood] = useState<number>(initial?.mood ?? 5);
+  const [pending, startTransition] = useTransition();
+  const [saved, setSaved] = useState<boolean>(initial != null);
+
+  function save(): void {
+    startTransition(async () => {
+      const result = await saveTodayCheckIn({ energy, sleep, hunger, mood });
+      if (result.ok) {
+        setSaved(true);
+        window.setTimeout(() => setSaved(false), 2500);
+      }
+    });
+  }
+
+  return (
+    <section className="border-ink/15 bg-carta-light/40 mb-10 border p-5">
+      <div className="flex flex-wrap items-baseline justify-between gap-4">
+        <div>
+          <p className="editorial-eyebrow">{t('checkInEyebrow')}</p>
+          <p className="font-display text-ink mt-2 text-base leading-snug">{t('checkInTitle')}</p>
+        </div>
+        {initial ? (
+          <span className="text-ink-soft font-mono text-[10px] uppercase tracking-widest">
+            {t('checkInAlreadyDone')}
+          </span>
+        ) : null}
+      </div>
+
+      <div className="mt-5 grid grid-cols-2 gap-x-6 gap-y-5 sm:grid-cols-4">
+        <Slider label={t('energy')} value={energy} onChange={setEnergy} />
+        <Slider label={t('sleep')} value={sleep} onChange={setSleep} />
+        <Slider label={t('hunger')} value={hunger} onChange={setHunger} />
+        <Slider label={t('mood')} value={mood} onChange={setMood} />
+      </div>
+
+      <div className="mt-5 flex flex-wrap items-center gap-3">
+        <Button type="button" variant="outline" onClick={save} disabled={pending} size="sm">
+          {pending ? t('saving') : initial ? t('checkInUpdate') : t('checkInSave')}
+        </Button>
+        {saved && !pending ? (
+          <span className="font-display text-oliva text-sm italic" role="status">
+            {t('checkInSaved')}
+          </span>
+        ) : null}
+      </div>
+    </section>
+  );
+}
+
+function Slider({
+  label,
+  value,
+  onChange,
+}: {
+  label: string;
+  value: number;
+  onChange: (n: number) => void;
+}) {
+  return (
+    <div>
+      <div className="flex items-baseline justify-between gap-2">
+        <p className="editorial-eyebrow">{label}</p>
+        <p className="text-ink font-mono text-sm tabular-nums">{value}/10</p>
+      </div>
+      <input
+        type="range"
+        min={1}
+        max={10}
+        value={value}
+        onChange={(e) => onChange(Number(e.target.value))}
+        className="mt-2 w-full cursor-pointer accent-current"
+      />
+    </div>
+  );
+}

apps/web/src/app/[locale]/tracking/page.tsx

@@ -6,10 +6,18 @@ import { setRequestLocale } from 'next-intl/server';
 import { Masthead } from '@/components/masthead';
 import { getServerSession } from '@/lib/auth';
 
-import { fetchWeightEntries } from './actions';
+import { fetchProfile } from '../profile/actions';
+
+import { fetchTodayCheckIn, fetchWeightEntries } from './actions';
+import { DailyCheckIn } from './daily-check-in';
 import { WeightEntryForm } from './weight-entry-form';
 import { WeightHistory } from './weight-history';
 
+type ProfileLike = {
+  weightGoalKg?: number;
+  alertWeightKg?: number | null;
+} | null;
+
 export default async function TrackingPage({ params: { locale } }: { params: { locale: string } }) {
   setRequestLocale(locale);
   const session = await getServerSession();
@@ -22,18 +30,35 @@ export default async function TrackingPage({ params: { locale } }: { params: { l
   if (!user?.disclaimerAcceptedAt) redirect('/welcome');
   if (!user.profile) redirect('/onboarding');
 
-  const entries = await fetchWeightEntries();
+  const [entries, profile, todayCheckIn] = await Promise.all([
+    fetchWeightEntries(),
+    fetchProfile(),
+    fetchTodayCheckIn(),
+  ]);
 
-  return <TrackingPageContent entries={entries} />;
+  return (
+    <TrackingPageContent
+      entries={entries}
+      profile={profile as ProfileLike}
+      todayCheckIn={todayCheckIn}
+    />
+  );
 }
 
 function TrackingPageContent({
   entries,
+  profile,
+  todayCheckIn,
 }: {
   entries: Awaited<ReturnType<typeof fetchWeightEntries>>;
+  profile: ProfileLike;
+  todayCheckIn: Awaited<ReturnType<typeof fetchTodayCheckIn>>;
 }) {
   const t = useTranslations('Tracking');
   const latest = entries[0] ?? null;
+  const goalKg = typeof profile?.weightGoalKg === 'number' ? profile.weightGoalKg : null;
+  const alertKg = typeof profile?.alertWeightKg === 'number' ? profile.alertWeightKg : null;
+  const alertActive = alertKg != null && latest != null && latest.weightKg >= alertKg;
 
   return (
     <div className="mx-auto min-h-screen max-w-5xl px-6 sm:px-10">
@@ -50,6 +75,23 @@ function TrackingPageContent({
 
         <div className="rule animate-rule-in my-10 [animation-delay:360ms]" />
 
+        <DailyCheckIn initial={todayCheckIn} />
+
+        {alertActive && alertKg != null && latest != null ? (
+          <aside className="border-pomodoro/40 bg-pomodoro/5 mb-10 border-2 border-dashed p-5">
+            <p className="editorial-eyebrow">{t('alertEyebrow')}</p>
+            <p className="font-display text-ink mt-3 text-base leading-snug">
+              {t('alertMessage', {
+                current: latest.weightKg.toFixed(1),
+                threshold: alertKg.toFixed(1),
+              })}
+            </p>
+            <p className="font-display text-ink-soft mt-2 text-sm italic leading-snug">
+              {t('alertHint')}
+            </p>
+          </aside>
+        ) : null}
+
         <div className="grid gap-12 md:grid-cols-12">
           <section className="animate-fade-up [animation-delay:300ms] md:col-span-7">
             <p className="editorial-eyebrow mb-6">{t('newEntry')}</p>
@@ -57,7 +99,7 @@ function TrackingPageContent({
           </section>
           <aside className="md:border-ink/15 animate-fade-up [animation-delay:420ms] md:col-span-5 md:border-l md:pl-10">
             <p className="editorial-eyebrow mb-6">{t('history')}</p>
-            <WeightHistory entries={entries} />
+            <WeightHistory entries={entries} goalKg={goalKg} />
           </aside>
         </div>
       </main>

apps/web/src/app/[locale]/tracking/weight-entry-form.tsx

@@ -91,7 +91,37 @@ export function WeightEntryForm({ latest }: { latest: WeightEntryRow | null }) {
         </div>
 
         <div className="space-y-6">
-          <p className="editorial-eyebrow">{t('measurements')}</p>
+          <div className="flex items-baseline justify-between gap-4">
+            <p className="editorial-eyebrow">{t('measurements')}</p>
+            <details className="group">
+              <summary className="text-ink-soft hover:text-ink cursor-pointer list-none font-mono text-[10px] uppercase tracking-widest underline decoration-[1.5px] underline-offset-[5px]">
+                {t('measurementsHelpToggle')}
+              </summary>
+              <div className="border-ink/15 bg-carta-light/40 mt-3 max-w-md border p-4">
+                <ul className="font-display text-ink-soft space-y-3 text-sm leading-relaxed">
+                  <li>
+                    <strong className="text-ink not-italic">{t('waist')}</strong>:{' '}
+                    {t('measurementGuides.waist')}
+                  </li>
+                  <li>
+                    <strong className="text-ink not-italic">{t('hips')}</strong>:{' '}
+                    {t('measurementGuides.hips')}
+                  </li>
+                  <li>
+                    <strong className="text-ink not-italic">{t('thigh')}</strong>:{' '}
+                    {t('measurementGuides.thigh')}
+                  </li>
+                  <li>
+                    <strong className="text-ink not-italic">{t('arm')}</strong>:{' '}
+                    {t('measurementGuides.arm')}
+                  </li>
+                </ul>
+                <p className="font-display text-ink-dim mt-4 text-xs italic leading-snug">
+                  {t('measurementGuides.tip')}
+                </p>
+              </div>
+            </details>
+          </div>
           <div className="grid grid-cols-2 gap-x-6 gap-y-8 sm:grid-cols-4">
             {(
               [

apps/web/src/app/[locale]/tracking/weight-history.tsx

@@ -1,3 +1,4 @@
+import { linearWeightTrend, projectGoalDate } from '@ketopath/shared';
 import { useTranslations } from 'next-intl';
 
 import type { WeightEntryRow } from './actions';
@@ -57,7 +58,19 @@ function Sparkline({ values, width = 280, height = 64 }: SparkProps) {
   );
 }
 
-export function WeightHistory({ entries }: { entries: WeightEntryRow[] }) {
+const ITALIAN_DATE = new Intl.DateTimeFormat('it-IT', {
+  day: 'numeric',
+  month: 'long',
+  year: 'numeric',
+});
+
+export function WeightHistory({
+  entries,
+  goalKg,
+}: {
+  entries: WeightEntryRow[];
+  goalKg?: number | null;
+}) {
   const t = useTranslations('Tracking');
   if (entries.length === 0) {
     return (
@@ -73,6 +86,18 @@ export function WeightHistory({ entries }: { entries: WeightEntryRow[] }) {
   const oldest = entries[entries.length - 1]!;
   const delta = newest.weightKg - oldest.weightKg;
 
+  const trend = linearWeightTrend(
+    [...entries].reverse().map((e) => ({ date: e.date, weightKg: e.weightKg })),
+  );
+  const projectedDate =
+    trend && goalKg != null
+      ? projectGoalDate({
+          currentKg: newest.weightKg,
+          goalKg,
+          slopeKgPerWeek: trend.slopeKgPerWeek,
+        })
+      : null;
+
   return (
     <div className="space-y-8">
       <div>
@@ -83,7 +108,7 @@ export function WeightHistory({ entries }: { entries: WeightEntryRow[] }) {
         </div>
       </div>
 
-      <div className="border-ink/10 grid grid-cols-2 gap-6 border-y py-5">
+      <div className="border-ink/10 grid grid-cols-2 gap-6 border-y py-5 sm:grid-cols-3">
         <div>
           <p className="editorial-eyebrow">{t('current')}</p>
           <p className="text-ink mt-2 font-mono text-3xl font-medium leading-none tracking-tight">
@@ -103,8 +128,32 @@ export function WeightHistory({ entries }: { entries: WeightEntryRow[] }) {
             <span className="font-display text-ink-soft ml-1 text-xs italic">kg</span>
           </p>
         </div>
+        {trend && trend.n >= 2 ? (
+          <div>
+            <p className="editorial-eyebrow">{t('weeklyTrend')}</p>
+            <p
+              className={`mt-2 font-mono text-3xl font-medium leading-none tracking-tight ${
+                trend.slopeKgPerWeek < 0
+                  ? 'text-oliva'
+                  : trend.slopeKgPerWeek > 0
+                    ? 'text-pomodoro'
+                    : 'text-ink'
+              }`}
+            >
+              {trend.slopeKgPerWeek > 0 ? '+' : ''}
+              {trend.slopeKgPerWeek.toFixed(2)}
+              <span className="font-display text-ink-soft ml-1 text-xs italic">kg/sett</span>
+            </p>
+          </div>
+        ) : null}
       </div>
 
+      {projectedDate && goalKg != null ? (
+        <p className="font-display text-ink-soft text-base italic leading-snug">
+          {t('projection', { kg: goalKg.toFixed(1), date: ITALIAN_DATE.format(projectedDate) })}
+        </p>
+      ) : null}
+
       <ul className="space-y-3">
         {entries.slice(0, 8).map((e) => (
           <li