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/requestlog_test.go

@@ -109,8 +109,7 @@ func TestRequestLog_AttributesPresent(t *testing.T) {
 	}
 }
 
-// The point of routing #2453 through the access log: behind a proxy, `remote`
-// must be the client rather than the proxy, and must agree with what the
+// Behind a proxy, the access log's `remote` must be the client rather than the proxy, and must agree with what the
 // Active-sessions surface records for the same request. Logs and UI
 // disagreeing about who connected is worse than either being wrong alone.
 func TestRequestLog_RemoteHonoursTrustedProxyDepth(t *testing.T) {
@@ -136,8 +135,8 @@ func TestRequestLog_RemoteHonoursTrustedProxyDepth(t *testing.T) {
 			want:       "203.0.113.200",
 		},
 		{
-			// The case that motivated the change: proxy on a PUBLIC address,
-			// which the pre-#2453 heuristic logged as the proxy forever.
+			// A proxy on a PUBLIC address: a "trust XFF only from private
+			// peers" heuristic would log the proxy forever.
 			name:       "depth 1 through a public-addressed proxy logs the client",
 			hops:       func() int { return 1 },
 			remoteAddr: "203.0.113.200:40000",