Move test resource classes out of MCP-Tests

[Gabriel-Darbord]

Summary

• move non-test support/resource classes from MCP-Tests to MCP-Tests-Resources
• keep MCP-Tests focused on actual SUnit test classes
• remove isolated unused test-resource probe/temp classes with no binding refs and no source mentions
• replace remaining fixture class-name-only usages with direct class references where needed

Verification

• P13 targeted tests: 283 passed
• P13 MCP-Tests: 681 passed
• no unreferenced non-test leaf classes remain in MCP packages
• git diff --check