The link watch checks the active document's linked files every two
seconds and as the window comes back to the front, so the separate check
on focus that #925 added (missing_links::after_focus and its asked-files
set) goes: with both, a change was acted on twice. The watch also
walks the document's links only when a look is due, not every frame, and
wakes the app every two seconds only while the document has links. The
doc comments of status and links::groups are back on their functions.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>