[ML 0.1/UI.04.11] - Validate full behaviour parity between Compose and legacy message list

[rafaeltonholo]

Blocked by

• [ML 0.1/UI.04.8] - Wire message item click to legacy navigation handler #10781
• [ML 0.1/UI.04.9] - Wire swipe actions to legacy swipe handlers #10782
• [ML 0.1/UI.04.10] - Verify selection mode and favourite toggle with legacy action mode #10783

Description

Once all wiring tickets are complete, a full parity validation is needed to confirm the Compose MessageListScreen behaves consistently with the legacy implementation across all interaction paths.

Acceptance Criteria

• Message loading displays the same data as legacy.
• Pull-to-refresh triggers sync and updates the list.
• Footer "load more" works correctly.
• Single message click opens the correct message/thread.
• Swipe actions (all types) execute correctly.
• Selection mode (enter, toggle, exit) works correctly.
• Star/favourite toggle persists correctly.
• Account indicator visibility is correct for unified folders.
• No regressions in existing legacy behaviour.

Out of Scope:

• Performance benchmarking.
• UI polish or design changes.