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/notifications/digest.go

@@ -15,10 +15,8 @@ import (
 	"git.fabledsword.com/bvandeusen/minstrel/internal/mailer"
 )
 
-// The email digest (#5346). Nothing is emailed per event. Operator,
-// 2026-10-08: "music and stuff coming in should land as a summary email and
-// not everytime same for a approvals the emails should be grouped by a
-// reasonable amount of time like an hour or so."
+// The email digest. Nothing is emailed per event: a steady stream of new
+// music or approvals would otherwise be a stream of emails.
 //
 // - EmailSummary kinds (new music) go out at most once a day, at the summary
 //   hour in the user's own timezone, listing everything since the last one.

internal/notifications/email_settings.go

@@ -9,7 +9,7 @@ import (
 	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
 )
 
-// EmailSettings are the digest's two knobs, in admin Settings (rule 25).
+// EmailSettings are the digest's two knobs, edited in admin Settings.
 type EmailSettings struct {
 	// SummaryHour is the local hour (0-23, in each user's own timezone) the
 	// daily new-music summary goes out.

internal/notifications/kinds.go

@@ -1,17 +1,16 @@
-// Package notifications is the one writer of the per-user notifications inbox
-// (M489, #726). Producers across the server call Notifier.Notify; nothing else
+// Package notifications is the one writer of the per-user notifications
+// inbox. Producers across the server call Notifier.Notify; nothing else
 // inserts into user_notifications.
 //
-// The event bus alone was fire-and-forget: a client that was not connected
-// when a request completed, or when tracks went missing, never heard of it. A
-// row here is the durable record. The bus only nudges open clients to come
-// and read it.
+// The event bus is fire-and-forget: a client that is not connected when a
+// request completes, or when tracks go missing, never hears of it. A row here
+// is the durable record. The bus only nudges open clients to come and read
+// it.
 package notifications
 
-// Kind names one sort of notification. The set is CHECK-gated in migration
-// 0073, swapped since by 0075 (rule 36): a new kind adds its value in a
-// migration of the same change, and TestEveryKindPassesTheSchemaChecks
-// fails until it does.
+// Kind names one sort of notification. The set is CHECK-gated in the schema:
+// a new kind adds its value (DROP + ADD of the CHECK) in a migration of the
+// same change, and TestEveryKindPassesTheSchemaChecks fails until it does.
 type Kind string
 
 const (
@@ -23,9 +22,8 @@ const (
 	KindScanFailed        Kind = "scan_failed"
 	KindTracksMissing     Kind = "tracks_missing"
 	KindDuplicatesFound   Kind = "duplicates_found"
-	// KindDuplicatesResolved: the duplicate resolver (M498) merged copies on
-	// its own. The operator asked for that to
-	// happen automatically; this is how it stays visible.
+	// KindDuplicatesResolved: the duplicate resolver merged copies on its
+	// own. This is how an automatic merge stays visible.
 	KindDuplicatesResolved Kind = "duplicates_resolved"
 	KindPlaybackErrors     Kind = "playback_errors"
 )

internal/notifications/notifier.go

@@ -17,7 +17,7 @@ import (
 // row lands for them. It is a nudge with no content: the client fetches the
 // inbox. A frame that carried the notification could not be told apart from
 // a repeat after a reconnect, and a frame nobody received is then one nobody
-// needed, because the client pulls on reconnect anyway (Roundtable #2535).
+// needed, because the client pulls on reconnect anyway.
 const EventCreated = "notification.created"
 
 // Recipients names who an event is for.

internal/notifications/notifier_db_test.go

@@ -146,9 +146,9 @@ func TestNotify_CoalescedCountAddsUpWhileUnread_AndStartsAfreshOnceRead(t *testi
 	require.True(t, rows[1].ReadAt.Valid)
 }
 
-// M542: an update says more, newest names first, without arriving again. A
-// moved created_at was announced again on the phone, and a cleared emailed_at
-// was emailed again.
+// An update says more, newest names first, without arriving again: a moved
+// created_at would announce it again on the phone, and a cleared emailed_at
+// would email it again.
 func TestNotify_ACoalescedUpdateMergesNamesAndKeepsItsArrival(t *testing.T) {
 	pool := testPool(t)
 	q := dbq.New(pool)
@@ -238,9 +238,9 @@ func TestMarkRead_ScopedToTheOwner_AndIdempotent(t *testing.T) {
 	require.Zero(t, unread)
 }
 
-// Every kind the code knows must pass both CHECKs in the real schema. This is
-// rule 36's guard: a kind added in Go without the migration fails here, not in
-// production at INSERT time.
+// Every kind the code knows must pass both CHECKs in the real schema: a kind
+// added in Go without its migration fails here, not in production at INSERT
+// time.
 func TestEveryKindPassesTheSchemaChecks(t *testing.T) {
 	pool := testPool(t)
 	q := dbq.New(pool)

internal/notifications/render.go

@@ -42,7 +42,7 @@ type Payload struct {
 	// read.
 	Count int64 `json:"count,omitempty"`
 	// Items name what Count counts, one each, newest first: "Weezer – Buddy
-	// Holly". A coalesced update puts its own in front and keeps ten (M542),
+	// Holly". A coalesced update puts its own in front and keeps ten,
 	// so the body can say which, not only how many.
 	Items []string `json:"items,omitempty"`
 	// Detail is free text: scan_failed's error message. Rows from before

internal/notifications/render_test.go

@@ -45,7 +45,7 @@ func TestRender_CoalescedCountsReadNaturally(t *testing.T) {
 	require.Equal(t, "Some tracks went missing", Render(KindTracksMissing, []byte(`{}`)).Title)
 }
 
-// M542: a notice says which, not only how many.
+// A notice says which, not only how many.
 func TestRender_NamesWhatChanged(t *testing.T) {
 	require.Equal(t, "No longer on disk: Weezer – Buddy Holly.",
 		render(KindTracksMissing, Payload{Count: 1, Items: []string{"Weezer – Buddy Holly"}}).Body)