chore: initial monorepo scaffold

Setup pnpm workspaces with apps/{web,api} placeholders and shared
packages: tsconfig, eslint-config, shared, ui, db. Includes Prettier,
ESLint, Husky pre-commit, lint-staged, EditorConfig, VSCode settings.

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

packages/shared/.eslintrc.cjs

@@ -0,0 +1,5 @@
+/** @type {import('eslint').Linter.Config} */
+module.exports = {
+  root: true,
+  extends: ['@ketopath/eslint-config'],
+};

packages/shared/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "@ketopath/shared",
+  "version": "0.0.0",
+  "private": true,
+  "type": "module",
+  "main": "./src/index.ts",
+  "types": "./src/index.ts",
+  "exports": {
+    ".": "./src/index.ts"
+  },
+  "scripts": {
+    "typecheck": "tsc --noEmit",
+    "lint": "eslint src --max-warnings=0"
+  },
+  "devDependencies": {
+    "@ketopath/eslint-config": "workspace:*",
+    "@ketopath/tsconfig": "workspace:*"
+  }
+}

packages/shared/src/index.ts

@@ -0,0 +1 @@
+export {};

packages/shared/tsconfig.json

@@ -0,0 +1,10 @@
+{
+  "extends": "@ketopath/tsconfig/base.json",
+  "compilerOptions": {
+    "outDir": "dist",
+    "rootDir": "src",
+    "composite": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist"]
+}