Plan per-mailbox billing and the personal-mailbox backend

Shipped

August 26, 2026 at 8:17 PM UTC

Author

Kamo

Commit

56d37a7

Plans B and C of 3. Self-review closed five gaps: nothing set mail_cost_mode, nothing server-side stopped a billing group buying mail add-ons, the invoice mailbox-count column had no task, and Plan C's OAuth work silently broke the service constructor its own tests call.