feat(reports): show chapter progress while a report is being written (BUG-601)

The worker already persists a phase ladder and durable per-section rows;
the waiting screen parsed the progress fields and rendered none of them.
Chapter progress now drives the screen: one cell per chapter rather than
a percentage bar, since the job percent jumps 0->30 and 90->100.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016P5RoqzmUQEbeC2qjAkeGr

frontend/src/app/api/reports/[reportId]/route.ts

@@ -57,9 +57,16 @@ async function resolvePersistenceForUser() {
     userId: user.id,
     persistence,
     jobs: createSupabasePersonalReportJobService(supabase),
-      listSections: async (ownerId: string, requestId: string) => {
+    // sectionId and attemptCount are consumed by resolveReportRead to derive
+    // reader-visible chapter state; neither is forwarded to the browser raw.
+    listSections: async (ownerId: string, requestId: string) => {
       const rows = await sections.list(ownerId, requestId);
-      return rows.map((row) => ({ status: row.status, lastErrorCode: row.lastErrorCode }));
+      return rows.map((row) => ({
+        sectionId: row.sectionId,
+        status: row.status,
+        attemptCount: row.attemptCount,
+        lastErrorCode: row.lastErrorCode,
+      }));
     },
     loadLongformAppendix: async (input: Readonly<{ userId: string; reportId: string }>) => {
       const appendixRead = await supabase