* feat(comments): paste/drop image attachments in comments + inline render (IDEA-1650)
Comment composers were plain textareas with no upload path, and comment
bodies rendered markdown without an attachment resolver — so a
`pad-attachment:UUID` reference would never display. This wires both
halves end to end:
- Compose: paste or drop files into the comment composer (ItemTimeline)
and the reply box (TimelineCommentCard). A shared helper
(commentAttachments.ts) splices an "Uploading…" placeholder at the
caret, uploads concurrently via the existing attachment API, and swaps
each placeholder for its `pad-attachment:UUID` markdown ref (image
syntax for image MIMEs, link/chip syntax otherwise — mirrors the
editor's split). Submit is gated while uploads are in flight.
- Display: ItemTimeline lazily HEAD-probes each referenced UUID (reusing
the editor's fetchAttachmentMetadata cache), builds a reactive
resolver, and threads it into renderMarkdown for comments and replies
so refs render as inline images / file chips.
- Orphan GC: comment uploads leave attachments.item_id NULL (like the
editor), but the GC reference scan only checked items.content/fields.
Renamed AttachmentReferencedInItems -> AttachmentReferenced and
extended it to scan comments.body, so a screenshot referenced only
from a comment isn't reclaimed after the grace period. Added
TestOrphanGC_KeepsAttachmentReferencedFromComment.
Follow-up refinement (thumbnails + click-to-expand lightbox) captured as
IDEA-1660.
* fix(comments): escape markdown-significant chars in attachment filenames per Codex review (round 1)
Filenames containing [ ] or backslash could break the generated
 markdown. P2 (grant-aware upload auth) is a
pre-existing endpoint-wide gap shared with the rich editor — tracked as
BUG-1661, not fixed here to keep the PR focused.
* fix(comments): preventDefault on dragover for file drops per Codex review (round 2)
Browsers only deliver a file drop to a custom target if its dragover
cancels the default; without it the page navigates to the file. Gated
on isFileDrag so in-textarea text drag-drop is unaffected.
xarmian
e179c595e4