Python: Filter response_format from MCP tool call kwargs

[giles17]

Motivation and Context

Filters out response_format from kwargs before forwarding to MCP servers, preventing serialization errors when using structured outputs with MCP tools.
Also added three unit tests for logging level configuration in MCP connections (unrelated to the PR's stated purpose).

Resolves #3483

Description

Contribution Checklist

• The code builds clean without any errors or warnings
• The PR follows the Contribution Guidelines
• All unit tests pass, and I have added new tests where possible
• Is this a breaking change? If yes, add "[BREAKING]" prefix to the title of the PR.

[markwallace-microsoft]

Python Test Coverage Report •

File	Stmts	Miss	Cover	Missing
packages/core/agent_framework
_mcp.py	388	53	86%	112, 174, 183, 246, 254, 275, 365, 432, 467, 469, 473–474, 476–477, 531, 546, 564, 605, 711, 724–729, 751, 772, 775–777, 792–793, 799–801, 820, 829, 832–834, 849–850, 854–858, 875–879, 1019
TOTAL	16249	2341	85%

Python Unit Test Overview

Tests	Skipped	Failures	Errors	Time
3484	221 💤	0 ❌	0 🔥	1m 7s ⏱️

[Copilot]

Pull request overview

This PR aims to fix a bug where MCP tool calls fail when non-serializable framework arguments like response_format are passed through. The fix adds response_format to the exclusion list in the call_tool method's filtering logic.

Changes:

• Added response_format to the framework kwargs exclusion set in MCPTool.call_tool() method
• Added three unit tests for logging level configuration in MCP connections (unrelated to the PR's stated purpose)

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
python/packages/core/agent_framework/_mcp.py	Adds response_format to the exclusion set when filtering kwargs before passing to MCP session
python/packages/core/tests/core/test_mcp.py	Adds three tests for MCP server logging level configuration (appears unrelated to response_format filtering)