[GrantFox][Medium] Add typed error boundaries for market data and wallet flows

Summary

Add typed error boundaries for market data and wallet flows

Why this matters

Unhandled failures can blank the app or expose internal details.

Scope

Add domain-specific boundaries, safe fallback states, retry policy, and correlation IDs.

Acceptance criteria

• Market, wallet, and settlement failures have distinct recovery UI.
• Unknown errors are safe.
• Retry is limited and contextual.
• Tests cover thrown errors and rejected promises.

Validation

Add regression coverage for existing behavior, failure modes, authorization boundaries, and compatibility. The implementation must pass the repository CI checks.

Non-goals

• Typo-only, formatting-only, or documentation-only changes.
• Unrelated refactors or dependency upgrades.
• Weakening existing security, authorization, CI, or production safeguards.

Contributor application

Before implementation, comment with relevant experience, a 1–4 bullet approach, and an estimate for opening the first draft PR. Wait for maintainer assignment before coding.

PR requirements

Use a feature branch, include Closes #<issue-number>, check every acceptance criterion, link criteria to code/tests, explain security and failure-mode considerations, and pass CI.

Reward-readiness

This is a substantive GrantFox campaign issue. Merge and CI success do not by themselves guarantee reward eligibility; final reward-readiness is determined by campaign review.

First locate the existing market data, wallet, and settlement flow entry points, error handling, and related tests; the issue does not name specific files. Read the current failure and authorization behavior before proposing an approach, then verify distinct recovery UI, safe unknown-error handling, contextual retry limits, correlation IDs, and coverage for thrown errors and rejected promises through the repository CI checks.