Merge #2701@142e496f5 (a failed lookup isn't "not found"; no timer on found libraries) into round3a-integration

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/control-protocol.md

@@ -194,8 +194,11 @@ background check found (`false`: moved, on a disconnected drive, a folder that c
 library; `null`: not checked yet, or the check couldn't tell, e.g. an unreadable catalog) and `checking` whether one
 is running: the command never looks at a folder itself. A failed open never marks a library missing (another program
 may have it). Recent libraries are checked in the
-background when the app starts, again after 30 s, and when the launch window opens; File ▸ Open Recent Library
-greys out only an entry a check found missing (an unreadable catalog or a failed open doesn't grey it out). `lastOpened`: ISO 8601, `null` when not known; kept in `ui.json` →
+background when the app starts (the first 8) and when the launch window opens; one not found is looked for again every
+30 s (a drive plugged back in), the others only when the window comes back to the front (a timer would wake external
+drives and shares). File ▸ Open Recent Library greys out only an entry a check found missing (not there, not a folder,
+no library in it); an unreadable catalog, a folder that refuses to be listed, a failed open or a lookup that failed
+(a share that timed out) doesn't grey it out. `lastOpened`: ISO 8601, `null` when not known; kept in `ui.json` →
 `settings.recentLibrariesOpened`. `{remove: path}` forgets one entry (an error if the list
 doesn't hold it) and `{clear: true}` (or `app.clearRecentLibraries`) all of them; nothing on disk is touched.