docs: library comments say what the scanner and resolver do, not how they came to be (#6277)

Rewrites the internal/library comment blocks to rule 32. Task, milestone,
decision and rule ids are gone; the incidents behind them are restated as
the constraint they left (why a file is deleted before its row, why the
missing mark is a mark, why duplicates block on duration). Counts and
album names from one library are dropped from production comments; test
comments keep the names their fixtures use. The tagReadVersion log keeps
each version's before and after, without the measurements.

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

internal/library/watcher.go

@@ -60,7 +60,7 @@ func classifyEvent(op fsnotify.Op, isDir, isAudio bool) watchAction {
 // because the walk alone only ever gave one of them: the walk re-visits every
 // path that EXISTS, which catches additions and edits, and the reconcile pass
 // that runs with it compares the whole tracks table against what the walk saw,
-// which is what catches removals (#2523). classifyEvent still ignores fsnotify
+// which is what catches removals. classifyEvent still ignores fsnotify
 // removals by design, so a deleted file surfaces at the next scan, not the
 // next inotify event.
 type Watcher struct {
@@ -71,7 +71,7 @@ type Watcher struct {
 }
 
 // NewWatcher watches the scanner's folders, and moves to the new ones when
-// they change in Settings (#6129).
+// they change in Settings.
 func NewWatcher(scanner *Scanner, enricher *coverart.Enricher, logger *slog.Logger) *Watcher {
 	return &Watcher{
 		scanner:  scanner,