* feat: Enhance chat streaming and tool call processing
- Added support for MongoDB checkpointer in the chat streaming workflow.
- Introduced functions to process tool call chunks and sanitize arguments.
- Improved event message creation with additional metadata.
- Enhanced error handling for JSON serialization in event messages.
- Updated the frontend to convert escaped characters in tool call arguments.
- Refactored the workflow input preparation and initial message processing.
- Added new dependencies for MongoDB integration and tool argument sanitization.
* fix: Update MongoDB checkpointer configuration to use LANGGRAPH_CHECKPOINT_DB_URL
* feat: Add support for Postgres checkpointing and update README with database recommendations
* feat: Implement checkpoint saver functionality and update MongoDB connection handling
* refactor: Improve code formatting and readability in app.py and json_utils.py
* refactor: Clean up commented code and improve formatting in server.py
* refactor: Remove unused imports and improve code organization in app.py
* refactor: Improve code organization and remove unnecessary comments in app.py
* chore: use langgraph-checkpoint-postgres==2.0.21 to avoid the JSON convert issue in the latest version, implement chat stream persistant with Postgres
* feat: add MongoDB and PostgreSQL support for LangGraph checkpointing, enhance environment variable handling
* fix: update comments for clarity on Windows event loop policy
* chore: remove empty code changes in MongoDB and PostgreSQL checkpoint tests
* chore: clean up unused imports and code in checkpoint-related files
* chore: remove empty code changes in test_checkpoint.py
* chore: remove empty code changes in test_checkpoint.py
* chore: remove empty code changes in test_checkpoint.py
* test: update status code assertions in MCP endpoint tests to allow for 403 responses
* test: update MCP endpoint tests to assert specific status codes and enable MCP server configuration
* chore: remove unnecessary environment variables from unittest workflow
* fix: invert condition for MCP server configuration check to raise 403 when disabled
* chore: remove pymongo from test dependencies in uv.lock
* chore: optimize the _get_agent_name method
* test: enhance ChatStreamManager tests for PostgreSQL and MongoDB initialization
* test: add persistence tests for ChatStreamManager with PostgreSQL and MongoDB
* test: add unit tests for ChatStreamManager initialization with PostgreSQL and MongoDB
* test: enhance persistence tests for ChatStreamManager with PostgreSQL and MongoDB to verify message aggregation
* test: add unit tests for ChatStreamManager with PostgreSQL and MongoDB
* test: add unit tests for ChatStreamManager initialization with PostgreSQL and MongoDB
* test: add unit tests for ChatStreamManager initialization with PostgreSQL and MongoDB
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Co-authored-by: Willem Jiang <willem.jiang@gmail.com>