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.go

@@ -45,13 +45,16 @@ type Item struct {
 
 // Page is one stored raw page: its slug, the URL it was fetched from, and the
 // bytes. HTML pages carry HTML; the JSON service page carries JSON and the
-// child's Compass userId (from the fetcher's meta file).
+// child's Compass userId (from the fetcher's meta file). FetchedAt is when the
+// fetcher stored the page, so a "Today" widget can be dated correctly even when
+// an old run is re-parsed.
 type Page struct {
-	Slug   string
-	URL    string
-	HTML   []byte
-	JSON   []byte
-	UserID string
+	Slug      string
+	URL       string
+	HTML      []byte
+	JSON      []byte
+	UserID    string
+	FetchedAt time.Time
 }
 
 // Parse turns the stored pages for one child into structured items. It fails,
@@ -96,30 +99,39 @@ func Parse(child string, pages []Page, loc *time.Location) ([]Item, error) {
 			items = append(items, got.items...)
 			recognised++
 		case PageLearningTasks:
-			if hasAuthoritativeTasks {
-				recognised++
-				continue
+			if !hasAuthoritativeTasks {
+				got, err := parseLearningTasks(child, p, loc)
+				if err != nil {
+					return nil, err
+				}
+				items = append(items, got...)
 			}
-			got, err := parseLearningTasks(child, p, loc)
+			// The child's own day widget is the per-child timetable (FR-16).
+			day, _, err := parseDayWidget(child, p, loc, p.FetchedAt)
 			if err != nil {
 				return nil, err
 			}
-			items = append(items, got...)
+			items = append(items, day...)
 			recognised++
 		case PageChildProfile:
 			// The React profile page has no server-rendered grid; when it does
 			// carry the legacy grid, use it. The JSON list supersedes it.
-			if hasAuthoritativeTasks {
-				recognised++
-				continue
+			if !hasAuthoritativeTasks {
+				got, found, err := extractLearningTasks(child, p, loc)
+				if err != nil {
+					return nil, err
+				}
+				if found {
+					items = append(items, got...)
+				}
 			}
-			got, found, err := extractLearningTasks(child, p, loc)
+			// The profile page carries the child's own "Today" widget: the
+			// authoritative per-child periods (FR-16).
+			day, _, err := parseDayWidget(child, p, loc, p.FetchedAt)
 			if err != nil {
 				return nil, err
 			}
-			if found {
-				items = append(items, got...)
-			}
+			items = append(items, day...)
 			recognised++
 		case PageHome:
 			got, err := parseNews(child, p, loc)