feat: Enhance backend with context management, error handling, and refactored code

[ogabrielluiz]

This pull request includes significant updates to the backend, focusing on enhancing context management, improving error handling, and refactoring code for better maintainability. The most important changes include the introduction of the AgentContext class, updates to the Component class for context handling, and various improvements to the graph and tracing services.

Check the added test for an example use case of the context.

Context Management Enhancements:

• src/backend/base/langflow/base/agents/context.py: Introduced the AgentContext class to manage agent context, including serialization and validation of language models.
• src/backend/base/langflow/custom/custom_component/component.py: Added methods to the Component class for managing context, including add_to_ctx, update_ctx, and _pre_run_setup. [1] [2] [3]

Error Handling Improvements:

• src/backend/base/langflow/base/embeddings/aiml_embeddings.py: Enhanced error messages in embed_documents to provide more detailed information.

Code Refactoring:

• src/backend/base/langflow/components/embeddings/aiml.py: Refactored imports to use the new module structure for AIMLEmbeddingsImpl.
• src/backend/base/langflow/components/embeddings/util/__init__.py: Removed redundant import for AIMLEmbeddingsImpl.

Graph Improvements:

• src/backend/base/langflow/graph/graph/base.py: Added context handling to the Graph class and improved cycle detection logic. [1] [2] [3] [4] [5] [6] [7] [8] [9] [10] [11]
• src/backend/base/langflow/graph/graph/runnable_vertices_manager.py: Added support for managing vertices in cycles. [1] [2] [3]

Tracing Service Updates:

• src/backend/base/langflow/services/tracing/langsmith.py: Improved tracing service to handle scenarios where the run tree is not ready. [1] [2] [3]

[italojohnny]

I ran the unit tests three times, and they consistently failed at the same points.

[codspeed-hq]

CodSpeed Performance Report

Merging #4286 will degrade performances by 14.64%

_{Comparing feat-context (06d79bf) with main (c5495c4)}

Summary

⚡ 2 improvements
❌ 2 regressions
✅ 11 untouched benchmarks

⚠️ Please fix the performance issues or acknowledge them on CodSpeed.

Benchmarks breakdown

	Benchmark	main	feat-context	Change
❌	test_invalid_run_with_input_type_chat	14.5 ms	16.1 ms	-10.16%
❌	test_successful_run_with_input_type_any	451.2 ms	528.5 ms	-14.64%
⚡	test_successful_run_with_input_type_text	450.9 ms	393.1 ms	+14.7%
⚡	test_successful_run_with_output_type_debug	500.3 ms	451.3 ms	+10.86%