fix: clear Kuudo tenant state on bearer swaps

[tspicer]

Summary

• bind each Kuudo bearer to persisted MCP tenant state with a provider-local fingerprint
• clear active identity, credentials, and profiles before tool execution when the bearer changes
• derive the discriminator with the existing salted 600,000-iteration PBKDF2 implementation
• reuse the derived fingerprint across nested middleware and provider operations within one request

Root cause

The inbound Kuudo middleware scoped the current API key for downstream provider calls, but the session bridge could hydrate identity and credentials selected under a previous bearer. The initial keyed HMAC discriminator fixed ownership tracking but triggered the repository's sensitive-data CodeQL policy.

Validation

• uv sync
• uv run ruff check --fix
• uv run pytest -q tests/unit/test_kuudo_provider.py tests/unit/test_inbound_auth.py tests/unit/test_authentication_middleware.py tests/unit/test_auth_session_bridge.py tests/unit/test_session_state.py tests/unit/test_session_scope_signaling.py

Result: 117 passed.

[chatgpt-codex-connector]

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