Adds MaildirMailboxSource reading new/ and cur/, wired through
source.maildir_dir and mailbox.protocol: maildir. Message identity is the
Maildir unique name without its :2,FLAGS suffix, so it survives the new/ to
cur/ move; it is carried on MailboxSourceMessage.dedup_uid and appended to the
message dedup key only when set, leaving fixture and IMAP keys unchanged.
Cursor ordering parses the Maildir delivery time instead of comparing names
lexically. mark_seen and a missing directory are rejected, matching the
read-only IMAP contract.
Also fixes the parse-failure path, which keyed identity on raw_message_ref.
A new/ to cur/ move rewrites that ref, so an unparseable message re-registered
as new on every rescan; it now prefers the source uid when one exists.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Plans a Maildir mailbox source, a containerized SMTP/IMAP test server,
deterministic test-user mailboxes, and end-to-end send-and-scan integration
tests, so automated test environments get mail accounts for test users without
a live provider.
Records the decision to use a purpose-built test server rather than integrating
s/qmail, and keeps bounce/complaint/deferral evidence on fixtures plus an
optional provider simulator tier.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
