Improve redaction screenshot UX

[neonwatty]

Summary

• Add developer-marked screenshot redaction messaging across screenshot options, area picker, auto mode, and annotation review.
• Mask marked fields during full-page, element, and selected-area capture without mutating their live values.
• Gate the Playwright-only html-to-image mock hook behind a test build flag and assert production bundles do not include it.
• Document redaction limitations and add a redaction fixture plus Playwright coverage for full-page, area, auto-mode, and real selected-area capture.

Local Verification

• npm run typecheck
• npm run test
• npm run lint (warnings only; existing max-lines/no-explicit-any warnings)
• npx playwright test e2e/widget.spec.ts -g "redaction|automatic full-page"
• npx playwright test e2e/widget.spec.ts
• npm run build:widget && ! rg "__bugdropMockToPng" public/widget.js public/widget.v1.js public/widget.v1.14.js public/widget.v1.14.0.js

Follow-up

• Architecture follow-up tracked in Follow-up: harden screenshot redaction architecture #152.
• New-user lab idea tracked in Build a BugDrop Lab for widget setup and screenshot/redaction testing #151.

[github-actions]

🎉 This PR is included in version 1.33.0 🎉

The release is available on GitHub release

Your semantic-release bot 📦🚀