Enhance Telegram bot with database integration and API features

- Added SQLite database support with Alembic for migrations.
- Implemented FastAPI for HTTP API to manage duties.
- Updated configuration to include database URL and HTTP port.
- Created entrypoint script for Docker to handle migrations and permissions.
- Expanded command handlers to register users and display duties.
- Developed a web application for calendar display of duties.
- Included necessary Pydantic schemas and SQLAlchemy models for data handling.
- Updated requirements.txt to include new dependencies for FastAPI and SQLAlchemy.

main.py

@@ -1,5 +1,7 @@
-"""Single entry point: build Application, register handlers, run polling."""
+"""Single entry point: build Application, run HTTP server + polling. Migrations run in Docker entrypoint."""
+import asyncio
 import logging
+import threading
 
 import config
 from telegram.ext import ApplicationBuilder
@@ -13,10 +15,30 @@ logging.basicConfig(
 logger = logging.getLogger(__name__)
 
 
+def _run_uvicorn(web_app, port: int) -> None:
+    """Run uvicorn in a dedicated thread with its own event loop."""
+    import uvicorn
+    loop = asyncio.new_event_loop()
+    asyncio.set_event_loop(loop)
+    server = uvicorn.Server(
+        uvicorn.Config(web_app, host="0.0.0.0", port=port, log_level="info"),
+    )
+    loop.run_until_complete(server.serve())
+
+
 def main() -> None:
     app = ApplicationBuilder().token(config.BOT_TOKEN).build()
     register_handlers(app)
-    logger.info("Bot starting (polling)...")
+
+    from api.app import app as web_app
+    t = threading.Thread(
+        target=_run_uvicorn,
+        args=(web_app, config.HTTP_PORT),
+        daemon=True,
+    )
+    t.start()
+
+    logger.info("Bot starting (polling)... HTTP API on port %s", config.HTTP_PORT)
     app.run_polling(allowed_updates=["message"])