feat: track Codex and Claude account usage

[rexdotsh]

Summary

• fetch Codex and Claude quotas automatically as part of GET /admin/accounts
• attach { fetchedAt, error, data } directly to each account for simple WebUI rendering
• use a 60-second in-process cache to avoid repeated upstream quota calls
• keep Codex profile, reset-credit, account identity, thread query, and reset-credit consume support
• persist only reset-credit redemption IDs/results for safe ambiguous retries
• add a forward cleanup migration for the quota tables already deployed by migration 0011

Verification

• bun test (94 pass)
• bun typecheck
• bun lint
• server and browser admin production bundles
• live production-backed /admin/accounts request returned attached Codex/Claude quotas
• migration 0012 applied successfully and verified only codex_reset_credit_redemptions remains