[Suggested Follow-ups][R1] Render follow‑up buttons + optimistic resolution in App

[inimaga]

Render follow‑up buttons + optimistic resolution in App:

• Register custom tags for parsing
• In PureReportActionItem, detect in originalMessage.html, render ActionableItemButtons, and on click:
  • Optimistically merge selected into the Concierge message HTML.
  • Post AddComment with the question text.
• Ensure LHN preview/push text strips follow‑up blocks.

Parent issue: https://github.com/Expensify/Expensify/issues/587219

[samranahm]

@inimaga Is this open for external contributors.

[inimaga]

@samranahm No its not.

[samranahm]

Got it, thank you!

[melvin-bot]

Triggered auto assignment to @roryabraham, see https://stackoverflow.com/c/expensify/questions/7972 for more details.