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/gc/worker.go

@@ -1,8 +1,6 @@
-// Package gc runs periodic garbage-collection / lifecycle sweeps
-// against tables that have NO writer-side close path or NO retention
-// policy. Each sweep addresses a drift finding from the 2026-06-02
-// audit (Scribe parent #552) and is idempotent — re-running it on
-// already-clean rows is a no-op.
+// Package gc runs periodic garbage-collection / lifecycle sweeps against
+// tables that have no writer-side close path or no retention policy. Each
+// sweep is idempotent: re-running it on already-clean rows is a no-op.
 //
 // One Worker handles all sweeps so a single long-tick goroutine
 // amortises the per-tick fixed cost. Each individual sweep is small
@@ -11,16 +9,16 @@
 // visible in the application log without an explicit metrics layer.
 //
 // Sweeps:
-//   - GcCloseStalePlayEvents      (#566)
-//   - GcClosePlaySessionsWithNoRecentEvents (#565)
-//   - GcExpireScrobbleQueueFailedRows (#567)
-//   - GcResetStuckSystemPlaylistRuns (#574)
-//   - GcDeleteExpiredPasswordResets   (#575)
-//   - GcDeleteExpiredSessions         (M462 #4978 — idle 30d / absolute 1y)
-//   - GcPruneDiagnostics              (M9 — diagnostics 30d retention)
-//   - GcDeleteExpiredSuggestionSnoozes (#2374 — snoozes expire, then go)
-//   - GcDeleteOrphanedCandidateArtistTags(+State) (#2376 — the similarity
-//     feed churns, so cached candidate tags outlive their candidates)
+//   - GcCloseStalePlayEvents
+//   - GcClosePlaySessionsWithNoRecentEvents
+//   - GcExpireScrobbleQueueFailedRows
+//   - GcResetStuckSystemPlaylistRuns
+//   - GcDeleteExpiredPasswordResets
+//   - GcDeleteExpiredSessions          (idle 30d / absolute 1y)
+//   - GcPruneDiagnostics               (30d retention)
+//   - GcDeleteExpiredSuggestionSnoozes (snoozes expire, then go)
+//   - GcDeleteOrphanedCandidateArtistTags(+State) (the similarity feed
+//     churns, so cached candidate tags outlive their candidates)
 package gc
 
 import (