test(e2e): Playwright photos-ready flow + visual evidence (#65)

Drive batch → pick calibration → Mask (Black) → Axis → Measure Calculate →
Photos ready against set1-48x2 fixtures on local vite preview. Capture
screenshots under tests/e2e/artifacts/; commit README + small evidence JPEGs.

frontend/package-lock.json

@@ -12,6 +12,7 @@
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@@ -494,6 +495,21 @@
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