feat(status): add stale transaction state with explicit refresh control - #988

Summary

Closes #936

This PR introduces a deterministic stale transaction state and an explicit user-driven refresh control for the draw-credit flow. It ensures that when network conditions or delays render a transaction status ambiguous, users receive clear feedback and a safe recovery path rather than facing silent data loss or an unrecoverable UI state.

Implementation Details

• State Model: Expanded the Transaction type union in draw-credit.types.ts and creditLine.ts to include the "stale" status.
• Design Tokens: Mapped "stale" to the existing accent color modifier and pending geometric pattern in TransactionStatus.tsx, adhering strictly to DESIGN_SYSTEM.md constraints against new inline hex values.
• Backward Compatibility: Introduced onRefresh as an optional prop (onRefresh?: () => void), ensuring the 17 existing E2E callers (e.g., RepayPage) remain completely unbroken.
• Consumer Wiring: Updated DrawCreditPage.tsx to handle the onRefresh callback, triggering a loading state and re-polling the ledger status deterministically. This explicitly locks the UI (setIsLoading(true)) to prevent concurrent state mutation loops.

Test Plan

• Maintained all 20 existing WCAG (1.4.1 / 4.1.3) accessibility pattern tests without degradation.
• Extended TransactionStatus.patterns.test.tsx (now 28 tests passing) to verify "stale" renders the correct accessible pattern and text ("Status Unknown").
• Verified the "Refresh Status" button appears only when both status === "stale" and the onRefresh prop are provided.
• Verified full TypeScript compilation passes cleanly (npm run build).