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.go

@@ -15,9 +15,9 @@ type adminQueueView struct {
 	Since *string `json:"since"`
 }
 
-// adminSummaryView is what the admin rail and the Overview's verdict read
-// (#5605): every queue an admin acts on, in one response, so each admin page
-// pays one cheap read for its rail.
+// adminSummaryView is what the admin rail and the Overview's verdict read:
+// every queue an admin acts on, in one response, so each admin page pays one
+// cheap read for its rail.
 type adminSummaryView struct {
 	Requests   adminQueueView `json:"requests"`
 	Reports    adminQueueView `json:"reports"`