fix: improve MCP schema compatibility and LLM guidance for reporting tools

[matt-landers]

This PR addresses two main issues with the Google Analytics MCP server:

1. Client Compatibility: Some MCP clients (e.g., Claude Desktop) expect additionalProperties in the tool input schema to be a boolean value rather than an object. I've added a recursive sanitize_mcp_schema_properties function to ensure all additionalProperties fields are converted to booleans.
2. LLM Guidance: To improve the reliability of tool calling for the run_report and run_realtime_report tools, I've explicitly marked essential fields as required in their schemas. This helps LLMs correctly identify the necessary arguments when generating tool calls.

Changes:

• Added sanitize_mcp_schema_properties utility to analytics_mcp/coordinator.py.
• Applied schema sanitization to all MCP tools.
• Explicitly defined required fields for run_report and run_realtime_report tools.

[emwhipple30-svg]

Done