Adds tests/agents/test_channel_agent_integration.py covering the full
stack from KnowledgeStore + IngestionPipeline through TwoStageRetriever,
KnowledgeSearchTool, and DeepResearchAgent into ChannelAgent/FakeChannel:
- test_quick_query_inline_response: asserts inline reply with meeting info
and no openjarvis:// escalation link
- test_deep_query_escalation_link: asserts openjarvis:// link is present
when engine issues a tool call and returns a long report
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>