ISSUE-024 — Flutter decision: wrap PWA, revive native, or retire

[shivaram19]

• Functional surgeon view: After PWA retention data is collected, a decision records whether to keep, wrap, or remove the Flutter app.
• Acceptance criteria:
  1. Retention and APK conversion data reviewed.
  2. Decision recorded in ADR.
  3. Code changes executed (wrap/retire/revive).
• Dependencies: ISSUE-012 (math PWA live), APK conversion metrics.