No blockers raised; hardening + clarity:
- client/mail.py: URL-encode the caller-supplied attachment_id
(quote(..., safe="")) — defense-in-depth against path traversal.
- server/mail.py: measure attachment content in UTF-8 bytes (not characters)
for the size cap and the sentinel message.
- scanner.py: bound _mail_cap_logged (insertion-ordered dict + oldest-first
eviction at 50k, mirroring _consent_backstop_done) so the cap-log dedup set
can't leak in a long-running multi-tenant process; reword the cap log to not
imply MAIL_SCAN_MAX_PER_MAILBOX is operator-tunable (it's the Mail OCS max).
- models/mail.py: comment why GetAttachmentResponse doesn't nest MailAttachment
(different OCS endpoint shape).
- mail_content.py: document format_mail_addresses' empty-entry skip contract.
_potentially_deleted doc_type-in-key remains tracked as Deck #376 (pre-existing
cross-cutting; reviewer confirmed deferral).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
