Mounts on Pro routers (trees, sessions, scripts, FlowPilot, etc.) and
returns 402 with structured detail when an account's subscription is
missing or locked. Allowlist bypasses billing/account/auth flows so
users can recover from a lapsed subscription.
Conftest now seeds a default Pro/active Subscription on test_user and
test_admin (delete-then-insert because the register endpoint already
creates a free/active sub by default). Two existing tests adapted to
the new seeded plan; tenant-isolation tests seed Subscription rows for
the accounts they create directly.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
