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/admin_summary_test.go

@@ -32,7 +32,7 @@ func getAdminSummary(t *testing.T, h *handlers, user dbq.User) (int, adminSummar
 }
 
 // The summary counts each queue an admin acts on and says since when the
-// oldest item has waited; an empty queue has no since (#5605).
+// oldest item has waited; an empty queue has no since.
 func TestAdminSummary_CountsTheQueuesAndSinceWhen(t *testing.T) {
 	h, _ := testHandlers(t)
 	admin := seedUser(t, h.pool, "admin", "pw", true)
@@ -64,8 +64,7 @@ func TestAdminSummary_CountsTheQueuesAndSinceWhen(t *testing.T) {
 }
 
 // Duplicates count what needs review: a cross-release group is kept and
-// linked by the resolver and waits on nobody (operator, 2026-10-19: the
-// headline said 3,479 when 536 needed review).
+// linked by the resolver and waits on nobody.
 func TestAdminSummary_DuplicatesCountOnlyWhatNeedsReview(t *testing.T) {
 	h, _ := testHandlers(t)
 	truncateLibrary(t, h.pool)