Export URL tokens in mini-export fixtures tripped secret-scan; replace with placeholders, stop regenerating them, and allowlist fixture paths for pre-redaction history.
Record the completed migration (channel map, mmetl/mmctl steps, caveats) and teach prepare-export to apply mattermost_channel renames plus user_emails for matching existing MM accounts.
Cherry-pick heuristics, manifest merge, global file search, scrollbar styling, and pytest/Playwright coverage unblock review and filtered export for mmetl.
