The v1 e2e suite (npm run test:e2e) hardcoded port 9110 for the
fixture_api.py and VITE_API_BASE_URL. P2's real damascus-api now binds
9110 on the developer host, so reuseExistingServer: true makes the
suite hit the real (empty) API and the tests fail with '0 matching'.
Move the fixture to 9111 by default; CI / clean hosts override with
FIXTURE_API_PORT=9110.
Also adds docs/plans/2026-06-24-p5-damascus-ui-v2.md (the P5 plan
that the worker will execute against), a test:unit script, and the
testing-library devDeps needed by the v2 component tests.
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