Security: Sophia Governor JSON Hardening

[MichaelSovereign]

Summary

This PR improves the robustness and security of the module by hardening the way it extracts and validates JSON responses from LLMs.

Changes

1. Secure JSON Extraction: Replaced loose regex-based extraction with a more controlled substring approach and added strict schema validation ().
2. Injection Mitigation: Prevents malformed or injected JSON payloads from influencing governance decisions.
3. Improved Reliability: Better handling of edge cases where LLMs return extra text before or after the JSON block.

Closes #7428