Phase 6b/7b: per-child decoded periods, separate brief blocks, idempotent calendar (AUD-119)

- Parse each child's own "Today" day widget for the timetable (FR-16); drop the
  school-wide week calendar's lesson grid and clean the leaked routine rows.
- Add the editable codes map (FR-17): subjects, rooms, teachers and period
  labels, seeded, an unknown code falls back to the raw code; `school codes` CLI.
- Brief: Finn's block first, then Harry's, four sections always present (FR-9);
  periods decoded into plain English; the undated tail is one counted line (FR-18).
- Calendar: write periods + work due + work overdue + major events, per child,
  on every pass. Identity is the stable per-item key, so a re-run never re-inserts
  (FR-8). morning-brief.sh now runs scan -> calendar push -> notify.
- Day-widget labels are 12-hour: 1-6 read as PM, fixing afternoon periods.

Proven live on .13: image 0.6.2-phase6b7b; both children's briefs decoded and
separate; 35 events in calendar.school; runs 2 and 3 of the scan added nothing.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

cmd/school/calendar.go

@@ -125,14 +125,11 @@ func calendarStatus(args []string) {
 		os.Exit(1)
 	}
 	now := time.Now().In(cfg.Location)
-	candidates, err := st.CalendarCandidates(ctx, nil, nil, calendar.StartOfDay(now), 0)
+	pendingEvents, err := calendar.Pending(ctx, st, calendar.Options{Now: now})
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "school calendar:", err)
 		os.Exit(1)
 	}
-	// Count events, not rows: a school-wide event is stored against each
-	// child but written once.
-	pendingEvents := len(calendar.GroupDuplicates(candidates))
 
 	if asJSON {
 		out := struct {
@@ -174,7 +171,7 @@ func calendarStatus(args []string) {
 	} else {
 		fmt.Printf("reachable       yes\n")
 	}
-	fmt.Printf("pending events  %d (important, not in the calendar yet)\n", pendingEvents)
+	fmt.Printf("pending events  %d (periods + due work + overdue + school events, not in the calendar yet)\n", pendingEvents)
 	fmt.Printf("pushes          %d (%d failed)\n", summary.Total, summary.Failed)
 	if summary.Last != nil {
 		state := "ok"
@@ -272,7 +269,11 @@ func printCalendarResult(res calendar.Result, loc *time.Location) {
 		if uid == "" {
 			uid = "-"
 		}
-		fmt.Printf("  item %-5d %-6s %-10s %-45s uid=%s\n", ev.ItemID, ev.Child, start, truncate(ev.Title, 45), uid)
+		kind := string(ev.Kind)
+		if kind == "" {
+			kind = "event"
+		}
+		fmt.Printf("  item %-5d %-8s %-6s %-10s %-45s uid=%s\n", ev.ItemID, kind, ev.Child, start, truncate(ev.Title, 45), uid)
 	}
 	for _, msg := range res.Errors {
 		fmt.Fprintf(os.Stderr, "FAILED: %s\n", msg)
@@ -285,9 +286,11 @@ func calendarEvents(args []string) {
 	fs := flag.NewFlagSet("calendar events", flag.ContinueOnError)
 	var (
 		days   int
+		past   int
 		asJSON bool
 	)
 	fs.IntVar(&days, "days", 14, "how many days ahead to read")
+	fs.IntVar(&past, "past", 1, "how many days back to read (overdue work sits in the past)")
 	fs.BoolVar(&asJSON, "json", false, "print the events as JSON")
 	_ = fs.Parse(args)
 
@@ -302,8 +305,9 @@ func calendarEvents(args []string) {
 	defer st.Close()
 
 	now := time.Now().In(cfg.Location)
+	start := now.AddDate(0, 0, -past)
 	end := now.AddDate(0, 0, days)
-	events, err := client.Events(ctx, now.Add(-24*time.Hour), end)
+	events, err := client.Events(ctx, start, end)
 	if err != nil {
 		fmt.Fprintln(os.Stderr, "school calendar:", err)
 		os.Exit(1)
@@ -321,7 +325,7 @@ func calendarEvents(args []string) {
 	if len(events) == 0 {
 		fmt.Printf("no events on %s between %s and %s\n",
 			cfg.Calendar.EntityID,
-			now.Format("2006-01-02 15:04"),
+			start.Format("2006-01-02 15:04"),
 			end.Format("2006-01-02 15:04"))
 		return
 	}