Fail the batch job when recording its end fails, and reconcile orphans

finishBatch now returns its error, and treats a batch that is no longer
running as one, so a batch job never ends succeeded with its batch still
running. A batch left pending or running with its job ended (process
stopped, or the final status write failed) is failed inside startBatch,
before the active batch is read, so it never blocks a manual or
replenish batch. This replaces the boot-only FailInterruptedBatches.

Document suggestions.name in the architecture schema summary.

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

cmd/server/main.go

@@ -150,11 +150,6 @@ func run(cfg config.Config, logger *slog.Logger) error {
 	if _, err := dinnerSvc.FailInterruptedGroundings(ctx); err != nil {
 		return err
 	}
-	// Likewise a suggestion batch with no job left to run it, so it does
-	// not block every later batch.
-	if _, err := suggestSvc.FailInterruptedBatches(ctx); err != nil {
-		return err
-	}
 	srv := &http.Server{
 		Addr:              cfg.HTTPAddr,
 		Handler:           router,