Keep merchant rules import button active offline for the all-skipped path

[MelvinBot]

Explanation of Change

The "Import" button in the merchant-rules import flow was disabled whenever the device was offline. This blocked the client-side-only path where every parsed row is a duplicate of an existing rule and/or references a category that doesn't exist — in that case ImportedMerchantRulesPage.importRules short-circuits and builds the "No merchant rules have been added…" confirmation modal locally, with no API call. Since no network is required for that path, the button should stay active offline.

The offline guard lived hard-coded in the shared ImportSpreadsheetColumns component (isDisabled={isOffline}), which is correct for its other consumers (categories, tags, members, per diem, company cards, wallet transactions) that need a live server round-trip. Rather than change behavior for everyone, this PR:

1. Adds an optional shouldDisableButtonWhenOffline prop (default true, preserving existing behavior for every other importer) to ImportSpreadsheetColumns, applied as isDisabled={shouldDisableButtonWhenOffline && isOffline}.
2. Passes shouldDisableButtonWhenOffline={false} from the merchant-rules page so its button stays active offline.

Fixed Issues

$ #96842
PROPOSAL: #96842 (comment)

Tests

• Verify that no errors appear in the JS console

Offline tests

QA Steps

// TODO: These must be filled out, or the issue title must include "[No QA]."

• Verify that no errors appear in the JS console

PR Author Checklist

• I linked the correct issue in the ### Fixed Issues section above
• I wrote clear testing steps that cover the changes made in this PR
  • I added steps for local testing in the Tests section
  • I added steps for the expected offline behavior in the Offline steps section
  • I added steps for Staging and/or Production testing in the QA steps section
  • I added steps to cover failure scenarios (i.e. verify an input displays the correct error message if the entered data is not correct)
  • I turned off my network connection and tested it while offline to ensure it matches the expected behavior (i.e. verify the default avatar icon is displayed if app is offline)
  • I tested this PR with a High Traffic account against the staging or production API to ensure there are no regressions (e.g. long loading states that impact usability).
• I included screenshots or videos for tests on all platforms
• I ran the tests on all platforms & verified they passed on:
  • Android: Native
  • Android: mWeb Chrome
  • iOS: Native
  • iOS: mWeb Safari
  • MacOS: Chrome / Safari
• I verified there are no console errors (if there's a console error not related to the PR, report it or open an issue for it to be fixed)
• I followed proper code patterns (see Reviewing the code)
  • I verified that comments were added to code that is not self explanatory
  • I verified that any new or modified comments were clear, correct English, and explained "why" the code was doing something instead of only explaining "what" the code was doing.
  • I verified any copy / text that was added to the app is grammatically correct in English. It adheres to proper capitalization guidelines (note: only the first word of header/labels should be capitalized), and is either coming verbatim from figma or has been approved by marketing (in order to get marketing approval, ask the Bug Zero team member to add the Waiting for copy label to the issue)
• If a new code pattern is added I verified it was agreed to be used by multiple Expensify engineers
• I followed the guidelines as stated in the Review Guidelines
• I tested other components that can be impacted by my changes (i.e. if the PR modifies a shared library or component like Avatar, I verified the components using Avatar are working as expected)
• If a new CSS style is added I verified that:
  • A similar style doesn't already exist
  • The style can't be created with an existing StyleUtils function (i.e. StyleUtils.getBackgroundAndBorderStyle(theme.componentBG))
• If new assets were added or existing ones were modified, I verified that:
  • The assets are optimized and compressed (for SVG files, run npm run compress-svg)
  • The assets load correctly across all supported platforms.
• If the PR modifies code that runs when editing or sending messages, I tested and verified there is no unexpected behavior for all supported markdown - URLs, single line code, code blocks, quotes, headings, bold, strikethrough, and italic.
• If the PR modifies a generic component, I tested and verified that those changes do not break usages of that component in the rest of the App (i.e. if a shared library or component like Avatar is modified, I verified that Avatar is working as expected in all cases)
• If the PR modifies a component related to any of the existing Storybook stories, I tested and verified all stories for that component are still working as expected.
• If the PR modifies a component or page that can be accessed by a direct deeplink, I verified that the code functions as expected when the deeplink is used - from a logged in and logged out account.
• If the PR modifies the UI (e.g. new buttons, new UI components, changing the padding/spacing/sizing, moving components, etc) or modifies the form input styles:
  • I verified that all the inputs inside a form are aligned with each other.
  • I added Design label and/or tagged @Expensify/design so the design team can review the changes.
• I added unit tests for any new feature or bug fix in this PR to help automatically prevent regressions in this user flow.
• If the main branch was merged into this PR after a review, I tested again and verified the outcome was still expected according to the Test steps.

Screenshots/Videos

Android: Native

Android: mWeb Chrome

iOS: Native

iOS: mWeb Safari

MacOS: Chrome / Safari

[MelvinBot]

I created this PR from an upstream branch since I don't have push access to your fork.

To take ownership of this branch and be able to push updates, run:

git remote add upstream https://github.com/Expensify/App.git
git fetch upstream claude-rulesImportOfflineButton
git checkout -b claude-rulesImportOfflineButton upstream/claude-rulesImportOfflineButton
git push -u origin claude-rulesImportOfflineButton

Then you can close this PR and open a new one from your fork.

[MelvinBot]

The only failing check is PR Author Checklist / checklist, and it's not something I can push a code fix for.

It fails because 0 out of 38 checklist items are checked. That check only passes once the PR Author Checklist boxes are ticked in the PR description — a manual step affirming the author/assignee has thought through each item. Ticking those boxes (and filling the ### Tests, ### Offline tests, and ### QA Steps sections, which are still empty/placeholders) is a human sign-off, so I won't do it on your behalf.

Every other check is passing or still running — none of them have genuinely failed.

To get this green: edit the PR description to complete the author checklist and write out the Tests / Offline tests / QA steps (or add [No QA] to the title if QA truly doesn't apply). The check re-runs automatically on edit.