fix: classify production proof auth boundary

[HomenShum]

Summary

• preflight production external-adapter runs for an explicitly approved Playwright storage state
• emit per-adapter structured authenticated_browser_state_required receipts instead of timing out on the blank-sheet CTA
• detect expired/missing auth in the live scenario with an actionable error
• preserve the rule that interactive browser credentials are not exported

Verification

• proofloopExternalAdapterAuthBootstrap: 3/3 tests passed
• both TypeScript checks passed
• exact production command exits in seconds and writes Finch, FinAuditing, and WorkstreamBench boundary receipts when auth state is absent