docs: server comments say what the code does, not how it came to be (#6277)

Comment blocks in cmd/minstrel and 30 smaller internal packages, rewritten
to rule 32's standard with each citation read in context: task, milestone
and rule ids go, and so do the stories they were attached to ("used to",
"Before #N", measurements from one install, quotes, pointers to Fabled
Librarian's records and to docs/superpowers files that are not in the
repo). Where a story wrapped a real constraint, the constraint stays as a
present-tense fact.

Comments that had gone stale are corrected:
- taste.Config: the tuned values are overlaid by internal/recsettings;
  it is no longer "a later follow-up".
- StorageConfig: the data dir holds art, caches and the stream secret,
  not only playlist covers.
- the Subsonic album list and getUser comments describe what they do
  today rather than a milestone that would change it.

Checked: the non-comment token stream of every changed file matches
HEAD, and gofmt -l is empty.

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

internal/playevents/writer_test.go

@@ -220,8 +220,8 @@ func TestRecordPlayEnded_DurationOver50Percent_NotSkip(t *testing.T) {
 }
 
 // A lost-response retry of an offline play (same user/track/started_at)
-// must not create a second history row. Guards the at-least-once replay
-// path added in the 2026-06-11 audit.
+// must not create a second history row: the offline replay is
+// at-least-once.
 func TestRecordOfflinePlay_DedupsByUserTrackStartedAt(t *testing.T) {
 	f := newFixture(t, 200_000)
 	ctx := context.Background()
@@ -491,7 +491,7 @@ func TestRecordPlayStarted_NoRotationWithoutSource(t *testing.T) {
 
 // seedSystemSnapshot creates a system playlist of the given variant
 // containing the fixture track with the given pick_kind, mimicking
-// what the builder persists (#1249, generalized #1270).
+// what the builder persists.
 func seedSystemSnapshot(t *testing.T, f fixture, variant, pickKind string) {
 	t.Helper()
 	pl, err := f.q.CreateSystemPlaylist(context.Background(), dbq.CreateSystemPlaylistParams{
@@ -567,7 +567,7 @@ func TestRecordPlayStartedWithSource_CrossVariant_PickKindNull(t *testing.T) {
 }
 
 func TestRecordPlayStartedWithSource_StampsDiscoverBucket(t *testing.T) {
-	// Discover stamps its candidate bucket (#1270); a discover play whose
+	// Discover stamps its candidate bucket; a discover play whose
 	// track is in the live snapshot freezes that bucket onto the play.
 	f := newFixture(t, 200_000)
 	seedSystemSnapshot(t, f, "discover", "dormant")