[No QA] Add cancel/delete vocabulary and SmartScan troubleshooting article

[MelvinBot]

Explanation of Change

This PR improves help site discoverability for users searching with "cancel" or "delete" terminology, and adds a new SmartScan troubleshooting article.

Cancel/delete vocabulary additions:

• New Expensify Close Account — Added "delete account", "cancel Expensify", "how to delete Expensify", "how to cancel Expensify" to keywords and clarified in the body that "closing" is the same as deleting/canceling.
• Expensify Classic Close or Reopen Account — Same keyword and body improvements for the Classic version.
• New Expensify Subscription — Added "cancel Expensify", "cancel plan", "delete subscription", "stop Expensify billing" to keywords and added a callout linking to Close Account for users who want to cancel entirely.
• Expensify Classic Billing Owner — Added "cancel subscription", "cancel billing", "stop billing", "delete workspace", "cancel Expensify" to keywords.

New article:

• Troubleshoot SmartScan and Receipt Issues — Covers failed scans, stuck scans, incorrect data extraction, tips for better mobile receipt photos, and when to manually enter an expense instead.

Fixed Issues

$ https://github.com/Expensify/Expensify/issues/623318

Tests

// TODO: The human co-author must fill out the tests before marking this PR as "ready for review".

Offline tests

N/A — docs-only changes.

QA Steps

// TODO: The human co-author must fill out the QA steps before marking this PR as "ready for review".

1. Visit the help site and search for "cancel account", "delete account", "cancel Expensify" — verify relevant articles appear.
2. Visit the new SmartScan troubleshooting article and verify it renders correctly.

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 any callback methods that were added or modified are named for what the method does and never what callback they handle (i.e. toggleReport and not onIconClick)
  • 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 shown in the product is localized by adding it to src/languages/* files and using the translation method
    • If any non-english text was added/modified, I used JaimeGPT to get English > Spanish translation. I then posted it in #expensify-open-source and it was approved by an internal Expensify engineer. Link to Slack message:
  • I verified all numbers, amounts, dates and phone numbers shown in the product are using the localization methods
  • 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)
  • I verified proper file naming conventions were followed for any new files or renamed files. All non-platform specific files are named after what they export and are not named "index.js". All platform-specific files are named for the platform the code supports as outlined in the README.
  • I verified the JSDocs style guidelines (in STYLE.md) were followed
• 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)
• I verified all code is DRY (the PR doesn't include any logic written more than once, with the exception of tests)
• I verified any variables that can be defined as constants (ie. in CONST.ts or at the top of the file that uses the constant) are defined as such
• I verified that if a function's arguments changed that all usages have also been updated correctly
• If any new file was added I verified that:
  • The file has a description of what it does and/or why is needed at the top of the file if the code is not self explanatory

Screenshots/Videos

N/A — docs-only changes, no UI modifications.

[OSBotify]

A preview of your ExpensifyHelp changes have been deployed to https://bc08941c.helpdot.pages.dev ⚡️

Updated articles:

• articles/expensify-classic/settings/Close-or-reopen-account
• articles/expensify-classic/workspaces/Assign-billing-owner-and-payment-account
• articles/new-expensify/billing-and-subscriptions/Add-a-payment-card-and-view-your-subscription
• articles/new-expensify/reports-and-expenses/Troubleshoot-SmartScan-and-Receipt-Issues
• articles/new-expensify/settings/Close-Account

[MelvinBot]

Fixed the failing spellcheck:

• Fixed typo Sart → SmartScan
• Rephrased headings to avoid Smartscans (not in cspell dictionary)
• Removed stray bullet point and extra parenthesis

[MelvinBot]

Fixed the spellcheck failure in the Classic article too (docs/articles/expensify-classic/expenses/Troubleshoot-SmartScan-Issues.md) — same typos as the New Expensify version (Sart, Smartscans, stray bullet).