v1.7.6: secondo tentativo fix avvio Windows pythonnet

Preload esplicito di pythonnet.load("netfx") in main.py PRIMA di
importare webview: il lazy-import del 'clr' fallisce sotto PyInstaller
perche' Python.Runtime.dll viene bundlata ma il loader netfx non sa
risolverla.

Aggiunti:
- main.py: bootstrap pythonnet con PYTHONNET_RUNTIME=netfx + load()
- build_windows.py: --clean rebuild, --collect-data pythonnet/clr_loader
  (per Python.Runtime.runtimeconfig.json e altri non-Python files),
  hidden-import clr_loader.netfx

build_windows.py

@@ -106,6 +106,9 @@ def run_pyinstaller():
         "--windowed",
         "--onedir",
         "--noconfirm",
+        # Forza rebuild pulita (senza, residui di build vecchi possono
+        # confondere il bundling di pythonnet/clr_loader).
+        "--clean",
     ]
     if icon_path.exists():
         cmd.extend(["--icon", str(icon_path)])
@@ -115,11 +118,28 @@ def run_pyinstaller():
         # Hidden imports per pywebview (EdgeChromium su Windows)
         "--hidden-import", "webview",
         "--hidden-import", "webview.platforms.edgechromium",
+        "--hidden-import", "webview.platforms.winforms",
         "--hidden-import", "clr",
+        "--hidden-import", "clr_loader",
+        "--hidden-import", "clr_loader.netfx",
+        "--hidden-import", "clr_loader.types",
+        "--hidden-import", "pythonnet",
         "--hidden-import", "requests",
-        # Collegamenti completi alle DLL .NET di pywebview/pythonnet
+        # Collegamenti completi: webview, pythonnet, clr_loader (porta
+        # con se Python.Runtime.dll + nethost.dll + runtimeconfig.json
+        # altrimenti winforms.py fallisce con "Failed to resolve
+        # Python.Runtime.Loader.Initialize ...")
         "--collect-all", "webview",
+        "--collect-all", "pythonnet",
+        "--collect-all", "clr_loader",
         "--collect-all", "mutagen",
+        # collect-data prende anche i file .json/.dll non-Python che
+        # collect-all potrebbe saltare (Python.Runtime.runtimeconfig.json
+        # in particolare).
+        "--collect-data", "pythonnet",
+        "--collect-data", "clr_loader",
+        "--copy-metadata", "pythonnet",
+        "--copy-metadata", "clr_loader",
         # Binari bundled
         *add_binaries,
         # Entry point

core/config.py

@@ -5,7 +5,7 @@ import os
 import sys
 from pathlib import Path
 
-VERSION = "v1.7.4"
+VERSION = "v1.7.6"
 
 
 APP_NAME = "MusicTools"

main.py

@@ -4,6 +4,29 @@ import os
 import sys
 from pathlib import Path
 
+# Windows: forza il caricamento del runtime pythonnet PRIMA di importare
+# webview. Con PyInstaller il lazy-loader fallisce con
+# "Failed to resolve Python.Runtime.Loader.Initialize" perche'
+# Python.Runtime.dll viene bundlata ma il loader non sa risolverla
+# senza l'inizializzazione esplicita. Fix conferma:
+# https://github.com/pythonnet/pythonnet/issues/2178
+if sys.platform == "win32":
+    try:
+        # Punta pythonnet ai propri file runtime dentro al bundle PyInstaller.
+        if getattr(sys, "frozen", False):
+            _bundle = Path(sys._MEIPASS)  # type: ignore[attr-defined]
+            _rt = _bundle / "pythonnet" / "runtime"
+            if _rt.exists():
+                os.environ["PYTHONNET_RUNTIME"] = "netfx"
+                os.environ["PYTHONNET_PYDLL"] = sys.executable
+        from pythonnet import load as _pythonnet_load
+        _pythonnet_load("netfx")
+        import clr  # noqa: F401  - inizializza il loader
+    except Exception as _e:
+        # Se il preload fallisce, lasciamo che webview tenti comunque:
+        # l'errore originale verra' mostrato con stack trace.
+        print(f"[bootstrap] preload pythonnet failed: {_e}")
+
 import webview
 
 from api.bridge import Api

requirements.txt

@@ -5,4 +5,4 @@ mutagen>=1.47.0
 pyobjc-core>=10.0 ; sys_platform == "darwin"
 pyobjc-framework-Cocoa>=10.0 ; sys_platform == "darwin"
 pyobjc-framework-WebKit>=10.0 ; sys_platform == "darwin"
-pythonnet>=3.0 ; sys_platform == "win32"
+pythonnet==3.0.3 ; sys_platform == "win32"