fix(gateway): complete lazy-install rebind for slack/feishu/matrix + add ensure_and_bind helper (#25038)

Fixes #25028.

The lazy-install hooks added in #25014 installed packages correctly but
failed to rebind module-level globals after install:

- Slack: missing aiohttp rebind → NameError on file uploads
- Feishu: none of the ~25 lark_oapi symbols rebound → TypeError on
  adapter instantiation
- Matrix: mautrix.types enums stayed as stubs → mismatched values at
  runtime

Introduces tools.lazy_deps.ensure_and_bind() — a DRY helper that
combines ensure() + importer-callable + globals().update(). This
eliminates the error-prone pattern of manually listing every global
that needs updating after lazy-install. Each platform adapter now
defines a single _import() function returning all bindings.

Also fixes: pyproject.toml [slack] extra was missing aiohttp (needed
by slack-bolt's async path).

pyproject.toml

@@ -83,7 +83,7 @@ hindsight = ["hindsight-client==0.6.1"]
 dev = ["debugpy==1.8.20", "pytest==9.0.2", "pytest-asyncio==1.3.0", "pytest-xdist==3.8.0", "pytest-split==0.11.0", "mcp==1.26.0", "ty==0.0.21", "ruff==0.15.10"]
 messaging = ["python-telegram-bot[webhooks]==22.6", "discord.py[voice]==2.7.1", "aiohttp==3.13.3", "slack-bolt==1.27.0", "slack-sdk==3.40.1", "qrcode==7.4.2"]
 cron = []  # croniter is now a core dependency; this extra kept for back-compat
-slack = ["slack-bolt==1.27.0", "slack-sdk==3.40.1"]
+slack = ["slack-bolt==1.27.0", "slack-sdk==3.40.1", "aiohttp==3.13.3"]
 matrix = ["mautrix[encryption]==0.21.0", "Markdown==3.10.2", "aiosqlite==0.22.1", "asyncpg==0.31.0", "aiohttp-socks==0.11.0"]
 cli = ["simple-term-menu==1.6.6"]
 tts-premium = ["elevenlabs==1.59.0"]