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/server/server_test.go

@@ -244,13 +244,11 @@ func TestRouter_AdminSubtreeNotShadowed(t *testing.T) {
 	}
 }
 
-// TestRouter_ReacquisitionSettingsSavedThroughTheAPIReachTheSweeper is a
-// regression test for #3936. Router() used to construct a
-// reacquisition.SettingsService of its own, so a save from the admin card
-// refreshed THAT instance's cache while the sweeper in cmd/minstrel/main.go
-// kept serving what it had loaded at boot. The card showed the new policy, the
-// feature kept running the old one, and only a restart reconciled them — the
-// exact thing rule 25 says a setting must not need.
+// TestRouter_ReacquisitionSettingsSavedThroughTheAPIReachTheSweeper: a
+// Router() that built a reacquisition.SettingsService of its own would refresh
+// THAT instance's cache on a save, while the sweeper in cmd/minstrel/main.go
+// kept serving what it loaded at boot. The card would show the new policy and
+// the feature run the old one until a restart.
 //
 // The assertion is made against the instance main.go hands the sweeper: save
 // through the router, then read that instance. A second service leaves it stale.