…ST API

Add support for function calling (tools) with Snowflake Cortex models that support it (e.g., Claude 3.5 Sonnet).

Changes:
- Add 'tools' and 'tool_choice' to supported OpenAI parameters
- Implement request transformation: OpenAI function format → Snowflake tool_spec format
- Implement response transformation: Snowflake content_list with tool_use → OpenAI tool_calls
- Add tool_choice transformation: OpenAI nested format → Snowflake array format

Request transformation:
- Transform tools from nested {"type": "function", "function": {...}} to Snowflake's {"tool_spec": {"type": "generic", "name": "...", "input_schema": {...}}}
- Transform tool_choice from {"type": "function", "function": {"name": "..."}} to {"type": "tool", "name": ["..."]}

Response transformation:
- Parse Snowflake's content_list array containing tool_use objects
- Extract tool calls with tool_use_id, name, and input
- Convert to OpenAI's tool_calls format with proper JSON serialization

Testing:
- Add 7 unit tests covering request/response transformations
- Add integration test for Responses API with tool calling
- All tests passing

Fixes issue #15218

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

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

)

* perf(router): add model_name index for O(1) deployment lookups

Add model_name_to_deployment_indices mapping to optimize _get_all_deployments()
from O(n) to O(1) + O(k) lookups.

- Add model_name_to_deployment_indices: Dict[str, List[int]]
- Add _build_model_name_index() to build/maintain the index
- Update _add_model_to_list_and_index_map() to maintain both indices
- Refactor to use idx = len(self.model_list) before append (cleaner)
- Optimize _get_all_deployments() to use index instead of linear scan

* test(router): add test coverage for _build_model_name_index

Add single comprehensive test for _build_model_name_index() function to fix
code coverage CI failure.

The test verifies:
- Index correctly maps model_name to deployment indices
- Handles multiple deployments per model_name
- Clears and rebuilds index correctly

Fixes: CI code coverage error for _build_model_name_index

Replace linear if-else provider routing with O(1) dispatcher lookup.
Migrate 12 providers to new architecture, achieving significant speedup.

update docs

update docs

…itellm into litellm_cleanup_main_2