schema-validated invoice marketplace form with inline errors and live regions

[mikewheeleer]

Summary

The invoice marketplace form validates loosely and announces nothing, so errors are easy to miss. Add schema validation with inline, accessible per-field errors and a summary live region.

Why this matters

Silent or inaccessible validation frustrates users and fails a11y. Schema-driven, announced errors are correct and inclusive.

Requirements

• Validate the invoice marketplace form against a schema; show inline per-field errors.
• Summarize errors in a live region and move focus to the first invalid field on submit.
• Errors clear as the user fixes each field.
• Submit is blocked while invalid, with a clear reason.

Technical guidance

• Associate each error with its input via aria-describedby.
• Announce the summary politely, not assertively, unless on submit.

Edge cases — each must have a test

• invalid field -> inline message + described-by wired
• submit with errors -> focus first invalid, summary announced
• fix a field -> its error clears
• all valid -> submits
• messages are specific per field

Acceptance criteria

• All requirements and every edge case above implemented and covered by tests
• New unit and integration tests; existing tests still pass and no regressions
• Structured, typed errors (no leaked internals; stable codes)
• npm run lint, npm test, and npm run build all pass locally
• Code follows the repo's existing conventions; no duplication or dead code
• Short docs/comments explaining the design and any non-obvious decisions
• PR description explains the approach and includes Closes #<issue>

Out of scope

• Async/server-side validation
• Multi-step wizard

Rewards

Part of the GrantFox OSS / Official Campaign (FWC26) — this task may be rewarded. PR quality is assessed by AI: depth, correctness under edge cases, meaningful tests, and clean design are what earn the reward. Shallow changes (typos, formatting, trivial docs) do not qualify.

[chuks68]

I would like to work on this issue because i am confident i can resolve the issue, having worked on and resolved similar issues. my eta is 4 hours