refactor: improve maintainability and testability of Vertex.build_params (#5808)

* refactor: Simplify parameter building in Vertex class using ParameterHandler

* feat: Add unit tests for ParameterHandler class and organize test structure

* refactor: rename openai.py to openai_chat_model.py to avoid overlapping names

- Introduced a new OpenAIModelComponent class to facilitate text generation using OpenAI's language models.
- Implemented various input fields including max_tokens, model_kwargs, json_mode, model_name, openai_api_base, api_key, temperature, and seed for enhanced configurability.
- Added methods for building the model and handling exceptions from OpenAI API calls.
- This component enhances the existing framework by integrating OpenAI's capabilities, allowing users to generate text with customizable parameters.

* refactor: update OpenAIModelComponent import paths to use openai_chat_model

- Changed import statements in model_input_constants.py, __init__.py, and test_tool_calling_agent.py to reflect the new OpenAIModelComponent location.
- This refactor improves code organization and clarity by ensuring consistent usage of the updated component structure.

* fix(param_handler): add error handling for invalid field types

- Introduced a ValueError exception for invalid field types in the ParameterHandler class.
- This change enhances robustness by ensuring that only valid field types are processed, improving error reporting for developers.

* feat: Support list-based file path handling in ParameterHandler

* test: Add comprehensive tests for ParameterHandler field processing

* feat: Enhance field skipping logic in ParameterHandler

Add support for skipping fields with type "other" in the parameter handling process

* refactor: Simplify storage service initialization and edge parameter processing

* refactor: Modernize parameter handling with pattern matching

Improve type handling and conversion in ParameterHandler by:
- Replacing conditional logic with pattern matching
- Simplifying type conversion for various field types
- Reducing nested conditionals
- Enhancing code readability and maintainability

* refactor: Update type hints for CycleEdge in parameter handling

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Co-authored-by: Ítalo Johnny <italojohnnydosanjos@gmail.com>

src/backend/tests/__init__.py

@@ -0,0 +1 @@
+"""Tests package for langflow."""