Refactor project structure and enhance Docker configuration

- Updated `.dockerignore` to exclude test and development artifacts, optimizing the Docker image size.
- Refactored `main.py` to delegate execution to `duty_teller.run.main()`, simplifying the entry point.
- Introduced a new `duty_teller` package to encapsulate core functionality, improving modularity and organization.
- Enhanced `pyproject.toml` to define a script for running the application, streamlining the execution process.
- Updated README documentation to reflect changes in project structure and usage instructions.
- Improved Alembic environment configuration to utilize the new package structure for database migrations.

main.py

@@ -1,88 +1,6 @@
-"""Single entry point: build Application, run HTTP server + polling. Migrations run in Docker entrypoint."""
-
-import asyncio
-import json
-import logging
-import threading
-import urllib.request
-
-import config
-from telegram.ext import ApplicationBuilder
-
-from handlers import group_duty_pin, register_handlers
-
-logging.basicConfig(
-    format="%(asctime)s - %(name)s - %(levelname)s - %(message)s",
-    level=logging.INFO,
-)
-logger = logging.getLogger(__name__)
-
-
-def _set_default_menu_button_webapp() -> None:
-    """Set the bot's default menu button to Web App so Telegram sends tgWebAppData when users open the app from the menu."""
-    if not (config.MINI_APP_BASE_URL and config.BOT_TOKEN):
-        return
-    menu_url = (config.MINI_APP_BASE_URL.rstrip("/") + "/app/").strip()
-    if not menu_url.startswith("https://"):
-        return
-    payload = {
-        "menu_button": {
-            "type": "web_app",
-            "text": "Календарь",
-            "web_app": {"url": menu_url},
-        }
-    }
-    req = urllib.request.Request(
-        f"https://api.telegram.org/bot{config.BOT_TOKEN}/setChatMenuButton",
-        data=json.dumps(payload).encode(),
-        headers={"Content-Type": "application/json"},
-        method="POST",
-    )
-    try:
-        with urllib.request.urlopen(req, timeout=10) as resp:
-            if resp.status == 200:
-                logger.info("Default menu button set to Web App: %s", menu_url)
-            else:
-                logger.warning("setChatMenuButton returned %s", resp.status)
-    except Exception as e:
-        logger.warning("Could not set menu button: %s", e)
-
-
-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:
-    # Menu button (Календарь) and inline Calendar button are disabled; users open the app by link if needed.
-    # _set_default_menu_button_webapp()
-    app = (
-        ApplicationBuilder()
-        .token(config.BOT_TOKEN)
-        .post_init(group_duty_pin.restore_group_pin_jobs)
-        .build()
-    )
-    register_handlers(app)
-
-    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", "my_chat_member"])
+"""Entry point: delegate to duty_teller.run.main(). Run with python main.py or duty-teller."""
 
+from duty_teller.run import main
 
 if __name__ == "__main__":
     main()