Fix unsafe type assertions in AgreementsFullStep

[KJ21-ENG]

Explanation of Change

Removes eight unsafe type assertions from AgreementsFullStep. Agreement field IDs now retain their compile-time relationship to each caller's form keys, and required-field errors are detected from the existing getFieldRequiredErrors result. The four checkbox IDs, validation behavior, custom error messages, draft handling, bank-statement validation, and rendered order are unchanged.

Fixed Issues

$ #94739
PROPOSAL: #94739 (comment)

Count change

Current baseline source:

• config/eslint/eslint.seatbelt.tsv at base e69182c5379d82f41b6c9d6b7c7237d2c1cb0dd1.

Before:

• src/components/SubStepForms/AgreementsFullStep.tsx: 8 violations

After:

• src/components/SubStepForms/AgreementsFullStep.tsx: 0 violations

Net reduction:

• 8 fewer unsafe type assertion violations.

TSV evidence:

• The verifier restored config/eslint/eslint.seatbelt.tsv byte-for-byte after confirming zero cleanup findings in the target.

Tests

1. Focused formatter and ESLint passed for src/components/SubStepForms/AgreementsFullStep.tsx.
2. The verifier-owned focused typecheck produced no authorized-path diagnostic; its only diagnostic was in unrelated src/components/AddressSearch/index.tsx.
3. The target is not matched by App Jest discovery, so focused Jest was not applicable.
4. git diff --check, changed-path proof, and generated-TSV restoration passed.
5. Independent scope, type-safety, and regression reviews were clean on the final diff.
6. Exact-head Fork CI run 32105010856 passed typecheck, lint, format, React Compiler, and Jest at signed commit 0293a7ece3647a5919384a552462b884e6ef96a0.

No manual application testing was performed; the evidence above is automated verification and independent review.

Offline tests

N/A: the agreement form is already disabled offline, this cleanup does not change networking or offline behavior, and no manual offline testing was performed.

QA Steps

1. Start either existing flow that reaches the Agreements step: non-USD reimbursement-account setup or global-reimbursements enablement.
2. Leave each agreement checkbox unchecked in turn, submit the form, and verify its existing specific required-field error appears.
3. Select all four agreement checkboxes and verify the form can continue as before.
4. In the non-USD flow, verify the existing required bank-statement upload behavior is unchanged when that input is shown.

PR Author Checklist

N/A rationale: no product behavior, copy, CSS, assets, networking, deeplink, Storybook story, messaging flow, generic component, or new feature/bug flow is intended to change. No manual platform, high-traffic-account, offline, console, screenshot/video, staging, or production testing was performed. Both existing callers and the agreement validation behavior were examined during planning and independent review, and exact-head CI covered the full repository checks. Every item below was considered against that scope.

• 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

N/A: no UI or visual behavior changed, and no screenshots or videos were produced.

Changed files (1)

• src/components/SubStepForms/AgreementsFullStep.tsx

[codecov]

Codecov Report

✅ Changes either increased or maintained existing code coverage, great job!

Files with missing lines	Coverage Δ
src/components/SubStepForms/AgreementsFullStep.tsx	0.00% <0.00%> (ø)
... and 9 files with indirect coverage changes