fix(coinpay): surface detailed error responses and propagate status fetch failures (fixes #93)

[Echolonius]

Summary

Fixes #93 by refactoring apps/web/lib/coinpay.ts to surface detailed error responses, log contextual status fetch failures, and expose getCoinpayPaymentDetailed() for structured error checking instead of silently swallowing failures with null.

Details

Problem

Previously, getCoinpayPayment() in apps/web/lib/coinpay.ts silently caught network exceptions and non-2xx HTTP responses, returning null without error propagation or structured error detail. Calling routes could not distinguish between a server misconfiguration, network timeout, or invalid payment payload vs a pending payment state.

Changes Made:

• Introduced getCoinpayPaymentDetailed(id) returning { ok: true, payment } | { ok: false, error }.
• Logged structured error context for HTTP non-2xx responses and payload parsing errors.
• Maintained 100% backward compatibility for existing callers via getCoinpayPayment(id).
• Added a full Vitest unit test suite in apps/web/lib/coinpay.test.ts covering non-2xx HTTP errors, network timeouts, valid payments, and backward compatibility.

Verification

• Vitest unit test suite passing (npx pnpm --filter @aiornot/web exec vitest run lib/coinpay.test.ts — 6/6 tests passing).
• Full TypeScript typecheck passing (pnpm run typecheck).

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🤖 Agent Payout Metadata (RFC #7)

• Solana USDC/SOL (Preferred): 3wbinZDnWmDxHMLtACNrskwZvRwg4KYbBWw1wuviXXHT
• Base USDC: 0xd194AB36E66BccDD80f19b56757CFe52EdEd49af

[ralyodio]

Closing — already shipped. The CoinPay change here landed verbatim via #108 (which included this branch's commits); apps/web/lib/coinpay.ts and apps/web/lib/coinpay.test.ts on master are byte-identical to this branch, so there's nothing left to merge. Thanks — getCoinpayPaymentDetailed is in and issue #93 is addressed.