Update Python requirement to 3.10+ for MCP compatibility

The MCP package requires Python 3.10 or higher. Updated:
- GitHub Actions workflow to test Python 3.10, 3.11, 3.12
- README.md badge to Python 3.10+
- CLAUDE.md prerequisites
- CONTRIBUTING.md prerequisites
- docs/MCP_SETUP.md prerequisites

This fixes the MCP installation error in CI:
'ERROR: No matching distribution found for mcp>=1.0.0'

MCP package versions 0.9.1+ all require Python 3.10+.

README.md

@@ -2,7 +2,7 @@
 
 [![Version](https://img.shields.io/badge/version-1.0.0-blue.svg)](https://github.com/yusufkaraaslan/Skill_Seekers/releases/tag/v1.0.0)
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT)
-[![Python 3.9+](https://img.shields.io/badge/python-3.9+-blue.svg)](https://www.python.org/downloads/)
+[![Python 3.10+](https://img.shields.io/badge/python-3.10+-blue.svg)](https://www.python.org/downloads/)
 [![MCP Integration](https://img.shields.io/badge/MCP-Integrated-blue.svg)](https://modelcontextprotocol.io)
 [![Tested](https://img.shields.io/badge/Tests-14%20Passing-brightgreen.svg)](tests/)