chore: make AIAuditBridge canonical

[Pigbibi]

Summary

• Make AIAuditBridge the canonical Quant AI audit bridge in README/deployment docs
• Keep legacy CodexAuditBridge only as migration fallback wording
• Parse GET request paths before query matching in the gateway service

Verification

• python3 -m ruff check scripts/run_monthly_codex_audit.py service/ai_gateway_service.py tests/test_run_monthly_codex_audit.py
• python3 -m unittest discover -s tests
• git diff --check

[github-actions]

🤖 Codex PR Review

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