feat: Meeting Assistant MVP - Complete implementation

Enterprise Meeting Knowledge Management System with:

Backend (FastAPI):
- Authentication proxy with JWT (pj-auth-api integration)
- MySQL database with 4 tables (users, meetings, conclusions, actions)
- Meeting CRUD with system code generation (C-YYYYMMDD-XX, A-YYYYMMDD-XX)
- Dify LLM integration for AI summarization
- Excel export with openpyxl
- 20 unit tests (all passing)

Client (Electron):
- Login page with company auth
- Meeting list with create/delete
- Meeting detail with real-time transcription
- Editable transcript textarea (single block, easy editing)
- AI summarization with conclusions/action items
- 5-second segment recording (efficient for long meetings)

Sidecar (Python):
- faster-whisper medium model with int8 quantization
- ONNX Runtime VAD (lightweight, ~20MB vs PyTorch ~2GB)
- Chinese punctuation processing
- OpenCC for Traditional Chinese conversion
- Anti-hallucination parameters
- Auto-cleanup of temp audio files

OpenSpec:
- add-meeting-assistant-mvp (47 tasks, archived)
- add-realtime-transcription (29 tasks, archived)

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

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

backend/app/config.py

@@ -0,0 +1,24 @@
+import os
+from dotenv import load_dotenv
+
+load_dotenv()
+
+
+class Settings:
+    DB_HOST: str = os.getenv("DB_HOST", "mysql.theaken.com")
+    DB_PORT: int = int(os.getenv("DB_PORT", "33306"))
+    DB_USER: str = os.getenv("DB_USER", "A060")
+    DB_PASS: str = os.getenv("DB_PASS", "")
+    DB_NAME: str = os.getenv("DB_NAME", "db_A060")
+
+    AUTH_API_URL: str = os.getenv(
+        "AUTH_API_URL", "https://pj-auth-api.vercel.app/api/auth/login"
+    )
+    DIFY_API_URL: str = os.getenv("DIFY_API_URL", "https://dify.theaken.com/v1")
+    DIFY_API_KEY: str = os.getenv("DIFY_API_KEY", "")
+
+    ADMIN_EMAIL: str = os.getenv("ADMIN_EMAIL", "ymirliu@panjit.com.tw")
+    JWT_SECRET: str = os.getenv("JWT_SECRET", "meeting-assistant-secret")
+
+
+settings = Settings()