TODO: Add testing/QA exception to agent spawn hooks

check-agent-spawn.sh blocks Playwright/testing agents because they don't naturally reference a Forgejo issue or plan slug. Testing agents verify work — they don't write code and shouldn't need the full scoping chain.

During westside Phase 15 validation, the Playwright agent was blocked twice before finding the right incantation. This adds friction to the QA cycle at exactly the moment you want fast feedback.

Add an exception path in check-agent-spawn.sh for prompts that contain Playwright/testing/validation keywords, or for qa agent type. The scoping gate exists to prevent unscoped code changes — testing agents can't make code changes, so the gate doesn't serve its purpose.