feat(max-bot): implement mock-based message flow with WIP file queue

- MAX API integration (long polling)
- MockPlatformClient for agent simulation
- File download & workspace storage
- Basic commands: /help, /start
- Attachment queue: add works, list/remove need testing

[WIP: attachment queue commands]
[MOCK-ONLY: requires real agent for production]

pyproject.toml

@@ -40,3 +40,6 @@ target-version = "py311"
 
 [tool.ruff.lint]
 select = ["E", "F", "I", "UP", "B"]
+
+[tool.setuptools.packages.find]
+include = ["core*", "adapter*", "sdk*"]