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/api/library_browse.go

@@ -7,18 +7,13 @@ import (
 	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
 )
 
-// genreCount is one row of the genre browse index (#367).
+// genreCount is one row of the genre browse index.
 //
 // Genres are the tag's own strings, split on [;,] but otherwise untouched — no
 // case folding and no synonym mapping. So "Rock" and "rock" can both appear,
-// as can "Rock/Pop" alongside "Rock" and "Pop". That's deliberate for v1: the
+// as can "Rock/Pop" alongside "Rock" and "Pop". That's deliberate: the
 // alternative is a normalisation table to invent and maintain, and the raw
 // spread has to be visible before anyone can judge whether it's a problem.
-//
-// The first look at that spread found it dominated by welded tokens like
-// "Alternative RockRock" — the scanner's own bug, not the operator's tagging
-// (#2499). Judge the "is a taxonomy needed" question (#2468) only against a
-// library re-scanned since that fix.
 type genreCount struct {
 	Genre      string `json:"genre"`
 	TrackCount int    `json:"track_count"`