feat(bot): точка входа, конфиг, главное меню, доступ для ADMIN_IDS, healthcheck

- config: pydantic-settings по подсистемам, ADMIN_IDS через запятую
- texts.yaml + валидация при старте (лишний/пропущенный ключ — ошибка сразу)
- меню: reply-клавиатура разделов (Участники — только админам), инлайн «Назад»/«Отмена»
  с редактированием сообщения на месте, /start, /menu, /help
- AccessMiddleware (outer) на сообщениях и кнопках: до #25 пускает только ADMIN_IDS,
  постороннему — одна фраза в сутки, устаревшие кнопки молча гасятся
- heartbeat-файл + HEALTHCHECK в Dockerfile; JSON-логи
- FSM пока в памяти (фабрика), хранилище в БД — в #5
- тесты на фейковой сессии aiogram через настоящий Dispatcher

Refs #4

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/fakes.py

@@ -0,0 +1,107 @@
+"""Offline Telegram: a fake aiogram session that records outgoing API calls and fabricates replies."""
+
+from collections.abc import AsyncGenerator
+from datetime import UTC, datetime
+from itertools import count
+from typing import Any
+
+from aiogram import Bot, Dispatcher
+from aiogram.client.session.base import BaseSession
+from aiogram.methods import EditMessageText, SendMessage, TelegramMethod
+from aiogram.methods.base import TelegramType
+from aiogram.types import Chat, Message, Update, User
+
+BOT_TOKEN = "42:TEST-TOKEN"
+
+
+class FakeSession(BaseSession):
+    def __init__(self) -> None:
+        super().__init__()
+        self.requests: list[TelegramMethod[Any]] = []
+        self._ids = count(1000)
+
+    async def make_request(
+        self,
+        bot: Bot,
+        method: TelegramMethod[TelegramType],
+        timeout: int | None = None,  # noqa: ASYNC109 - signature fixed by aiogram BaseSession
+    ) -> TelegramType:
+        self.requests.append(method)
+        if isinstance(method, SendMessage | EditMessageText):
+            chat_id = method.chat_id if isinstance(method.chat_id, int) else 0
+            return Message(  # type: ignore[return-value]
+                message_id=next(self._ids),
+                date=datetime.now(UTC),
+                chat=Chat(id=chat_id, type="private"),
+                text=method.text,
+            )
+        return True  # type: ignore[return-value]
+
+    async def stream_content(
+        self,
+        url: str,
+        headers: dict[str, Any] | None = None,
+        timeout: int = 30,  # noqa: ASYNC109 - signature fixed by aiogram BaseSession
+        chunk_size: int = 65536,
+        raise_for_status: bool = True,
+    ) -> AsyncGenerator[bytes, None]:  # pragma: no cover - not used
+        raise NotImplementedError
+        yield b""
+
+    async def close(self) -> None:
+        pass
+
+    def sent(self, method_type: type[TelegramMethod[Any]]) -> list[Any]:
+        return [r for r in self.requests if isinstance(r, method_type)]
+
+
+class TgClient:
+    """Feeds updates through a real Dispatcher (filters, middlewares, FSM) on top of FakeSession."""
+
+    def __init__(self, dp: Dispatcher) -> None:
+        self.dp = dp
+        self.session = FakeSession()
+        self.bot = Bot(BOT_TOKEN, session=self.session)
+        self._update_ids = count(1)
+        self._message_ids = count(1)
+
+    @staticmethod
+    def user(tg_id: int) -> dict[str, Any]:
+        return {"id": tg_id, "is_bot": False, "first_name": f"u{tg_id}", "username": f"u{tg_id}"}
+
+    async def send(self, tg_id: int, text: str) -> None:
+        message = {
+            "message_id": next(self._message_ids),
+            "date": int(datetime.now(UTC).timestamp()),
+            "chat": {"id": tg_id, "type": "private"},
+            "from": self.user(tg_id),
+            "text": text,
+        }
+        if text.startswith("/"):
+            cmd = text.split()[0]
+            message["entities"] = [{"type": "bot_command", "offset": 0, "length": len(cmd)}]
+        await self._feed({"message": message})
+
+    async def press(self, tg_id: int, data: str, message_text: str = "section") -> None:
+        callback = {
+            "id": str(next(self._update_ids)),
+            "from": self.user(tg_id),
+            "chat_instance": "ci",
+            "data": data,
+            "message": {
+                "message_id": next(self._message_ids),
+                "date": int(datetime.now(UTC).timestamp()),
+                "chat": {"id": tg_id, "type": "private"},
+                "from": {"id": 42, "is_bot": True, "first_name": "tgit"},
+                "text": message_text,
+            },
+        }
+        await self._feed({"callback_query": callback})
+
+    async def _feed(self, payload: dict[str, Any]) -> None:
+        update = Update.model_validate({"update_id": next(self._update_ids), **payload}, context={"bot": self.bot})
+        await self.dp.feed_update(self.bot, update)
+
+
+def as_user(tg_id: int) -> User:
+    return User(id=tg_id, is_bot=False, first_name=f"u{tg_id}")