- Remove temp-xxx optimistic inserts from submitComment/submitReply
- Wait for API response, then insert real comment into timeline
- Add Loader2 spinner to comment/reply submit buttons during loading
- Remove hover card from Markdown.tsx (will be handled via NodeView later)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The migration from tiptap-markdown to @tiptap/markdown in 38e92040
broke comment creation. The old package stored getMarkdown() on
editor.storage.markdown, but the official @tiptap/markdown extension
adds it directly to the editor instance (editor.getMarkdown()).
This caused getEditorMarkdown() to always return "", making the
submit button permanently disabled and preventing any comments.
Also fix stale submitting ref in useIssueTimeline dependency array.
