[Change Approver: Phase 2] Implement Bulk Change Approver Flow for Search page

[marcaaron]

cc @garrettmknight

Bulk Change Approver (Frontend-only)

• Enable admins to change approvers in bulk on the Reports page
• We’ll add a new bulk “Change approver” option on the Reports page when admins select multiple Processing reports. When selected, we’ll show all options in the ‘Change approver’ menu.
• If an admin selects reports that are already assigned to the new approver they've chosen, those reports will be left unchanged. Only reports currently assigned to a different approver will be updated.
• For example, if a selected Processing report is already assigned to the admin and they confirm the "Bypass approver" option, no changes will be made. Since the report is already in the desired state, the action will be silently ignored.

The Change Approver feature already works so we are mainly looking to have the same exact feature here, but as a bulk action.

Requirements

• Let users apply one new approver to many reports in a single flow.
• User can take control or re-route to another approver.
• Only one approver can be applied to many reports in bulk.
• User should only be able to make changes they are permitted to make if reports across policies are selected.

Mockups

Issue Owner

Current Issue Owner: @greg-schroeder

[melvin-bot]

Triggered auto assignment to @greg-schroeder (NewFeature), see https://stackoverflowteams.com/c/expensify/questions/14418#:~:text=BugZero%20process%20steps%20for%20feature%20requests for more details. Please add this Feature request to a GH project, as outlined in the SO. Remember to draft any necessary HelpDot updates by following the instructions here.

[melvin-bot]

⚠️ It looks like this issue is labelled as a New Feature but not tied to any GitHub Project. Keep in mind that all new features should be tied to GitHub Projects in order to properly track external CAP software time ⚠️

[melvin-bot]

Triggered auto assignment to Design team member for new feature review - @dannymcclain (NewFeature)

[QichenZhu]

Update: started working on this and will share the ETA soon.

[QichenZhu]

Update: PR drafted (#75729) and will be open for review early next week.