Fabric Inbox 0.8.2

A second pass: the live server's own error log, the 0.8.1 changes read again, and the core mail
paths. Every fix has a test that fails without it.

• Mail is not lost to a Durable Object reset. A message that arrived a minute after a deploy
  failed with "storage operation exceeded timeout" and was never delivered again (seen in the live
  log, 2026-09-28). A delivery now retries once after such a reset; it is still stored only once.
• A forgery is spam even from a sender you allowed. Mail that fails its domain's DMARC (reject or
  quarantine), or claims one of your domains without passing its checks, no longer passes because
  the domain is on Never spam. Never spam still wins over everything else. When the spam check
  itself cannot run, the message is screened by the model instead of being treated as clean.
• A long attachment name no longer makes a message impossible to receive (names are cut to 200
  bytes, keeping the extension).
• A long message reads whole in its conversation, as it already did on its own.
• The same email is not shown twice when its copy in another inbox falls on the next page.
• Gmail mail with only an HTML part is sorted into categories by its text, not its subject alone.
• "You have written to this sender" now means the whole address (it matched a part of another).
• Replying to mail with no Message-ID no longer puts an internal id into the reply's headers.
• Relays: the sign-in a relay was moved off is revoked an hour later without waiting for another
  connect; an upgrade cut off half-way is tried again; the hourly limit on upgrades is per account;
  the relay status shows the current relay; a refusal while another sign-in change runs answers 409.