refactor: review fixes and code improvements

- Add shared proxy module (bot/utils/proxy.py) to eliminate duplicate SOCKS5 parsing
- Fix AI client: escape HTML before Markdown→HTML conversion, unify timeouts,
  make health check optional and disabled by default, handle 429 retries
- Fix ai.py: correct forwarded message handling (aiogram 3.x forward_origin),
  pass relevant summaries via extra_system_content
- Fix dialogue.py: only respond to Astra's messages, use system context instead
  of prompt injection, answer on the limit message before phase transition
- Fix voice.py: load Whisper model in thread pool, safe WAV path generation
- Improve database.py: composite indexes, Boolean is_active, upsert file_id cache,
  add context cleanup helper
- Update weather.py and yadisk_download.py to use shared proxy connector
- Update yadisk.py: validate URL before cache clear, add download size limit,
  wrap sync file ops in to_thread
- Reuse S3 client via lru_cache
- Update setup_commands with /aiclear and /aiuser
- Update README, Dockerfile (Python 3.11), docker-compose (mount models)
- Pin dependency versions, remove unused httpx[socks]
- Add basic pytest tests for layout converter and voice normalization

bot/routers/moderation.py

@@ -1,9 +1,17 @@
+import logging
+
 from aiogram import Router, F
 from aiogram.types import Message
 
-from bot.utils.database import add_sticker_message, ban_user_stickers, is_user_sticker_banned
+from bot.utils.database import (
+    add_sticker_message,
+    ban_user_stickers,
+    is_user_sticker_banned,
+)
 from config import MODERATION_LIMIT
 
+logger = logging.getLogger(__name__)
+
 router = Router()
 
 
@@ -13,13 +21,28 @@ async def handle_sticker_or_gif(message: Message):
     chat_id = message.chat.id
 
     if await is_user_sticker_banned(user_id, chat_id):
-        await message.delete()
+        try:
+            await message.delete()
+            logger.info(
+                "Deleted sticker/gif from banned user | user=%d chat=%d",
+                user_id,
+                chat_id,
+            )
+        except Exception as exc:
+            logger.warning("Could not delete sticker/gif: %s", exc)
         return
 
     count = await add_sticker_message(user_id, chat_id)
+    logger.debug("Sticker/gif count | user=%d chat=%d count=%d", user_id, chat_id, count)
 
     if count >= MODERATION_LIMIT:
         await ban_user_stickers(user_id, chat_id)
+        logger.info(
+            "Sticker/gif ban triggered | user=%d chat=%d count=%d",
+            user_id,
+            chat_id,
+            count,
+        )
         await message.answer(
             f"⚠️ {message.from_user.full_name}, вы превысили лимит стикеров/GIF!\n"
             "Отправка стикеров и GIF ограничена на 5 минут.",