fix: Improve Whisper model status verification and PyInstaller builds

- Add robust model cache verification (check model.bin + config.json)
- Add new status messages: model_cached, incomplete_cache, model_error
- Forward model status events to frontend for better UI feedback
- Add clean_build_cache() to remove stale spec files before build
- Add --clean flag to PyInstaller commands
- Change sidecar from --onefile to --onedir for faster startup
- Add missing hidden imports: onnxruntime, wave, huggingface_hub.utils

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

sidecar/build.py

@@ -1,29 +1,66 @@
 #!/usr/bin/env python3
 """
 Build script for creating standalone transcriber executable using PyInstaller.
+Uses --onedir mode for faster startup compared to --onefile.
 """
 
 import subprocess
 import sys
 import os
+import shutil
+
+
+def clean_build_cache(script_dir):
+    """Clean old build artifacts that may cause stale spec file issues."""
+    dirs_to_clean = [
+        os.path.join(script_dir, "build"),
+        os.path.join(script_dir, "__pycache__"),
+    ]
+    files_to_clean = [
+        os.path.join(script_dir, "build", "transcriber.spec"),
+    ]
+
+    for f in files_to_clean:
+        if os.path.exists(f):
+            print(f"Removing old spec file: {f}")
+            os.remove(f)
+
+    for d in dirs_to_clean:
+        pycache = os.path.join(d)
+        if os.path.exists(pycache) and "__pycache__" in pycache:
+            print(f"Removing cache: {pycache}")
+            shutil.rmtree(pycache)
 
 
 def build():
     """Build the transcriber executable."""
-    # PyInstaller command
+    script_dir = os.path.dirname(os.path.abspath(__file__))
+
+    # Clean old build cache to avoid stale spec file issues
+    clean_build_cache(script_dir)
+
+    # PyInstaller command with --onedir for faster startup
     cmd = [
         sys.executable, "-m", "PyInstaller",
-        "--onefile",
+        "--onedir",
+        "--clean",  # Clean PyInstaller cache before building
         "--name", "transcriber",
         "--distpath", "dist",
         "--workpath", "build",
         "--specpath", "build",
+        # Core dependencies
         "--hidden-import", "faster_whisper",
         "--hidden-import", "opencc",
         "--hidden-import", "numpy",
         "--hidden-import", "ctranslate2",
         "--hidden-import", "huggingface_hub",
+        "--hidden-import", "huggingface_hub.utils",
         "--hidden-import", "tokenizers",
+        # ONNX Runtime for VAD
+        "--hidden-import", "onnxruntime",
+        # Audio processing
+        "--hidden-import", "wave",
+        # Collect data files
         "--collect-data", "faster_whisper",
         "--collect-data", "opencc",
         "transcriber.py"
@@ -32,10 +69,12 @@ def build():
     print("Building transcriber executable...")
     print(f"Command: {' '.join(cmd)}")
 
-    result = subprocess.run(cmd, cwd=os.path.dirname(os.path.abspath(__file__)))
+    result = subprocess.run(cmd, cwd=script_dir)
 
     if result.returncode == 0:
-        print("\nBuild successful! Executable created at: dist/transcriber")
+        print("\nBuild successful!")
+        print("Executable created at: dist/transcriber/transcriber.exe (Windows) or dist/transcriber/transcriber (Linux)")
+        print("\nNote: The Whisper model will be downloaded on first run if not cached.")
     else:
         print("\nBuild failed!")
         sys.exit(1)