feat: Implement payment notification system and API structure

- Added notifications for successful payments in `api/core/notifications.py`.
- Created main API entry point in `api/main.py` with FastAPI integration.
- Established routing structure in `api/routes/__init__.py` and `api/routes/pally.py` for handling payment callbacks.
- Developed billing handlers in `bot/handlers/billing.py` and `bot/handlers/buy.py` for subscription management.
- Introduced state management for user interactions in `bot/states/`.
- Created user interface elements in `bot/keyboards/` for navigation and payment processing.
- Set up middleware for dependency injection in `bot/middlewares/di.py`.
- Added support for user commands and interactions in `bot/handlers/common.py` and `bot/handlers/support.py`.
- Implemented logging and error handling throughout the bot's functionality.
- Created entry point script for API server in `entrypoints/api.sh`.

bot/middlewares/di.py

@@ -0,0 +1,26 @@
+from collections.abc import Awaitable, Callable
+from typing import Any
+
+from aiogram import BaseMiddleware
+from aiogram.types import TelegramObject
+from sqlalchemy.ext.asyncio import async_sessionmaker
+
+from schemas.di import DependenciesDTO
+
+
+class DIMiddleware(BaseMiddleware):
+    def __init__(self, deps: DependenciesDTO, session_factory: async_sessionmaker) -> None:
+        self.deps = deps
+        self.session_factory = session_factory
+
+    async def __call__(
+        self,
+        handler: Callable[[TelegramObject, dict[str, Any]], Awaitable[Any]],
+        event: TelegramObject,
+        data: dict[str, Any],
+    ) -> Any:
+        data["deps"] = self.deps
+
+        async with self.session_factory() as session:
+            data["session"] = session
+            return await handler(event, data)