Issue #212: feat: Implement LangChain message trimming

[dereck-symmetry]

This issue implements a new feature where LangChain message trimming is implemented.
The changes can be tested by Claude in an automated fashion by deployment. It can also be manually tested.

#718 is related to this issue. However the fix for that is NOT implemented here.

Closes #212
Refs #718

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality
  to not work as expected)
• Documentation update
• Infrastructure/deployment change
• [X ] Performance improvement
• Code refactoring

Project Area(s) Affected

• bases/
• components/
• projects/
• orchestrators/
• frontends/
• deployments/
• cloudformation/ or sam/ templates
• reference_data/
• scripts/
• test/ or e2e/
• Database schema (migrations)
• API endpoints
• Documentation (docs/, READMEs, ARCHITECTURE.md, CLAUDE.md)

Checklist

• commit message follows commit guidelines (see commitlint.config.mjs)
• documentation is changed or added (in /docs directory)
• code passes linting checks (uv run ruff check)
• code passes formatting checks (uv run ruff format)
• code passes type checking (uv run ty check)
• pre-commit hooks have been run successfully
• API changes: base (Python code) documentation in docs/
  and project README updated

Testing

• Manual testing performed
• Automated tests added/updated
• Integration testing completed

Additional Notes

Testing found a new possible bug with 1-org deployments. Author will create a new issue and discuss with the dev team.

Note that testing for this PR uses LLM for automated testing.