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>

internal/parse/parse_test.go

@@ -175,23 +175,20 @@ func TestParseCalendar(t *testing.T) {
 	if err != nil {
 		t.Fatalf("parseCalendar: %v", err)
 	}
-	if len(items) != 2 {
-		t.Fatalf("got %d items, want 2", len(items))
+	// The week calendar is school-wide, so its lesson grid is dropped: a
+	// child's own periods come from that child's day widget (FR-16). Only the
+	// real school event survives.
+	if len(items) != 1 {
+		t.Fatalf("got %d items, want 1 (the routine lesson is not a per-child period)", len(items))
 	}
 	if items[0].Type != TypeEvent {
 		t.Errorf("type = %q", items[0].Type)
 	}
 	if got := items[0].DueAt.Format("2006-01-02 15:04"); got != "2026-10-15 18:00" {
-		t.Errorf("event 1 time = %s", got)
+		t.Errorf("event time = %s", got)
 	}
 	if items[0].Title != "End of Year Concert - HALL - KSH" {
-		t.Errorf("event 1 title = %q", items[0].Title)
-	}
-	if items[1].Subject != "11HLEGB5" || items[1].Teacher != "LHT" {
-		t.Errorf("event 2 subject/teacher = %q/%q", items[1].Subject, items[1].Teacher)
-	}
-	if got := items[1].DueAt.Format("15:04"); got != "14:06" {
-		t.Errorf("event 2 time = %q", got)
+		t.Errorf("event title = %q", items[0].Title)
 	}
 }
 
@@ -430,3 +427,87 @@ func TestParseReconcilesOverdueWithHome(t *testing.T) {
 		t.Fatal("Parse accepted a home page with no record of the child (FR-12)")
 	}
 }
+
+// dayWidgetFixture is the per-child "Today" widget Compass renders on a child's
+// own profile page. The child is Finn (Year 7).
+const dayWidgetFixture = `<html><body>
+<div class="x-panel compass-day-calendar x-cal-panel" id="calendardaywidget-1055">
+  <div class="x-toolbar">Today</div>
+  <div class="calendardaywidget-1055-day-bd-evt-a x-cal-default calendar-event-93806 custom-event ext-cal-evt activity-type-1 ext-event-no-roll" style="left:0%;width:100%;top:95.8px;height:48.1px;">
+    <span class="ext-evt-bd" lang="en-GB">8:55: 1 - 7SCF - H14LAB - KNI</span>
+  </div>
+  <div class="calendardaywidget-1055-day-bd-evt-b x-cal-default calendar-event-93737 custom-event ext-cal-evt activity-type-1 ext-event-no-roll" style="left:50%;width:50%;top:145px;height:44px;">
+    <span class="ext-evt-bd" lang="en-GB">9:54: 2 - 7DESF - B1 - PSI</span>
+  </div>
+  <div class="calendardaywidget-1055-day-bd-evt-c x-cal-default calendar-event-93755 custom-event ext-cal-evt activity-type-1 ext-event-no-roll" style="left:0%;width:100%;top:321.6666666666667px;height:48px;">
+    <span class="ext-evt-bd" lang="en-GB">1:26: 4 - 7PEF - GYM4 - LTA</span>
+  </div>
+</div>
+</body></html>`
+
+// TestParseDayWidgetIsPerChild proves FR-16: a child's periods come from that
+// child's own day widget, and the school-wide week calendar's lesson grid is
+// never stored against the child.
+func TestParseDayWidgetIsPerChild(t *testing.T) {
+	loc := melbourne(t)
+	fetched := time.Date(2026, 10, 16, 7, 0, 0, 0, loc)
+	pages := []Page{
+		{Slug: PageChildProfile, URL: "https://nhs-vic.compass.education/Records/User.aspx?userId=4242", HTML: []byte(dayWidgetFixture), FetchedAt: fetched},
+		{Slug: PageCalendar, URL: "https://nhs-vic.compass.education/Organise/Calendar/", HTML: []byte(calendarFixture), FetchedAt: fetched},
+	}
+	items, err := Parse("Finn", pages, loc)
+	if err != nil {
+		t.Fatalf("Parse: %v", err)
+	}
+
+	leaked := 0
+	periods := 0
+	for _, it := range items {
+		if it.Subject == "11HLEGB5" {
+			leaked++
+		}
+		if it.SourcePage == PageChildProfile && it.Type == TypeEvent {
+			periods++
+			if it.DueAt == nil || it.DueAt.In(loc).Format("2006-01-02") != "2026-10-16" {
+				t.Errorf("period %q dated %v, want 2026-10-16", it.Title, it.DueAt)
+			}
+			if it.SourcePage != PageChildProfile {
+				t.Errorf("period %q source page = %q, want %q", it.Title, it.SourcePage, PageChildProfile)
+			}
+		}
+	}
+	if leaked != 0 {
+		t.Errorf("Finn's items carry %d Year 11 lesson(s) from the school-wide calendar", leaked)
+	}
+	if periods != 3 {
+		t.Errorf("Finn has %d periods, want 3", periods)
+	}
+}
+
+// TestDayWidgetParsesRoomAndTeacher proves the label is split into its parts so
+// the brief can decode them.
+func TestDayWidgetParsesRoomAndTeacher(t *testing.T) {
+	loc := melbourne(t)
+	fetched := time.Date(2026, 10, 16, 7, 0, 0, 0, loc)
+	items, found, err := parseDayWidget("Finn", Page{Slug: PageChildProfile, HTML: []byte(dayWidgetFixture), FetchedAt: fetched}, loc, fetched)
+	if err != nil || !found {
+		t.Fatalf("parseDayWidget: found=%v err=%v", found, err)
+	}
+	if len(items) != 3 {
+		t.Fatalf("got %d periods, want 3", len(items))
+	}
+	if items[0].Subject != "7SCF" {
+		t.Errorf("subject = %q", items[0].Subject)
+	}
+	if items[0].Title != "1 - 7SCF - H14LAB - KNI" {
+		t.Errorf("title = %q", items[0].Title)
+	}
+	if got := items[0].DueAt.In(loc).Format("15:04"); got != "08:55" {
+		t.Errorf("start = %q, want 08:55", got)
+	}
+	// The printed clock is 12-hour: the 1:26 period is 1:26 PM (the grid
+	// offset is the authority).
+	if got := items[2].DueAt.In(loc).Format("15:04"); got != "13:26" {
+		t.Errorf("afternoon start = %q, want 13:26", got)
+	}
+}