[No QA] Docs updates for E/A#94899 Odometer tab-switch discard changes FAQ

[MelvinBot]

Docs update for E/A#94899

PR #94899 adds a Discard changes? confirmation modal that appears when a user switches away from the Odometer tab in the Distance request flow with unsaved readings or images.

The Distance Expenses help article already documents the Odometer flow in detail (entering readings, attaching images, save-for-later), so this PR adds a single FAQ entry describing the new confirmation behavior.

What changed

• Added a new FAQ entry — "What happens if I switch tabs with unsaved odometer readings?" — to Distance-Expenses.md, explaining:
  • Switching tabs with unsaved odometer readings/images shows a Discard changes? confirmation.
  • Discard changes clears entries and switches tabs; Cancel keeps you on the Odometer tab.
  • With no readings/images entered, tab switching happens immediately with no confirmation.

All UI labels (Discard changes?, Discard changes, Cancel, Odometer, GPS, Map, Manual) were verified against the source code: src/languages/en.ts (discardChangesConfirmation) and the tab definitions in the PR.

@Julesssss, please review the files changed and confirm they reflect the current behavior. Then mark this PR Ready for review.

[OSBotify]

A preview of your ExpensifyHelp changes have been deployed to https://d1e22965.helpdot.pages.dev ⚡️

Updated articles:

• articles/new-expensify/reports-and-expenses/Distance-Expenses

[Julesssss]

Definitely not necessary