docs: add 5 critical tasks to living memory for bug fixes and improvements

Add comprehensive documentation for critical issues:
- Fix crate name "unwind" bug in MCP mode (getCrateSummary schema override)
- Ensure universal auto-ingestion for all crate-querying tools
- Implement ingestion completion tracking with re-ingestion
- Fix pre-ingestion MCP control and misleading health messages
- Enhance fallback ingestion schema for version comparison

Updates across all living memory files:
- Tasks.json: 5 new critical tasks with dependencies and implementation details
- Architecture.md: Document ingestion tracking, auto-ingestion patterns, MCP control
- ResearchFindings.json: Add research findings from task investigation
- UsefulInformation.json: Document error solutions and lessons learned

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: Peter