docs: api comments say what the endpoints do, not how they came to be (#6277)

Rewrites the internal/api comment blocks to rule 32: task, milestone and
rule ids gone, the stories behind them restated as the constraint they
left, stale references corrected (the stream secret is wired from config,
the timezone handler already refreshes the scheduler, the Android app is
the native client, the design docs cited are not in the repo). Also
rewraps comment lines over 80 columns left by the earlier batches.

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

internal/wanted/match.go

@@ -18,11 +18,11 @@ import (
 
 // Matching a library album to its MusicBrainz release group.
 //
-// Music from any mainstream source was matched against MusicBrainz on its
-// way in, so nearly every album has a group. The ids its tags carry are
-// taken as they are. Without them, the groups called what the album is called, from
-// the artist's discography and then from a search, are checked against the
-// album's own tracks, and the one its tracks agree with is taken.
+// Music from any mainstream source was matched against MusicBrainz on its way
+// in, so nearly every album has a group. The ids its tags carry are taken as
+// they are. Without them, the groups called what the album is called, from the
+// artist's discography and then from a search, are checked against the album's
+// own tracks, and the one its tracks agree with is taken.
 
 // Match methods, as library_album_matches records them.
 const (