feat: continue offline checklist progress (Closes #909)

frontend/authored-outbox.js

@@ -61,6 +61,21 @@ function createAuthoredOutbox({ storage, fetchJson, coordinator, backgroundSync,
         throw new Error('A review for this saved head is already queued. Open Drafts to inspect or discard it first.');
       }
     }
+    if (message.kind === 'issue-content') {
+      const queuedContent = items.find(item => item.kind === 'issue-content' && item.status === 'queued' &&
+        item.ownerLogin === ownerLogin && item.repository === String(message.repository || '') &&
+        item.number === Number(message.number || 0));
+      if (queuedContent) {
+        const replacement = {
+          ...queuedContent,
+          operationId: String(requestedOperationId || makeId()).slice(0, 128),
+          title: String(message.title || ''),
+          body: String(message.body || ''),
+        };
+        write(items.map(item => item.id === queuedContent.id ? replacement : item), mirror);
+        return replacement;
+      }
+    }
     if (items.length >= maxItems) throw new Error('Message outbox is full. Send or discard a queued message first.');
     const id = String(requestedOperationId || makeId()).slice(0, 128);
     const item = {
@@ -107,6 +122,7 @@ function createAuthoredOutbox({ storage, fetchJson, coordinator, backgroundSync,
   }
 
   async function enqueueDurably(message) {
+    const previousItems = read();
     const item = enqueue(message, false);
     if (message.attachment && ['update-reply', 'update-reply-read'].includes(message.kind) &&
         (!backgroundSync?.reconcile || !backgroundSync?.requestSync)) {
@@ -128,7 +144,7 @@ function createAuthoredOutbox({ storage, fetchJson, coordinator, backgroundSync,
     try {
       await backgroundSync.reconcile(durableItems, 'authored');
     } catch (error) {
-      write(read().filter(candidate => candidate.id !== item.id), false);
+      write(previousItems, false);
       throw error;
     }
     try {

frontend/background-issue-sync.js

@@ -105,6 +105,11 @@ function createIssueSyncStore({
           };
           incoming.set(current.id, replacement);
         }
+        if (current.kind === 'issue-content' && replacement.kind === 'issue-content' &&
+            current.operationId !== replacement.operationId && current.status === 'sending' &&
+            Number(current.claimUntil) > Number(now())) {
+          throw new Error('Checklist sync is already delivering. Retry this change.');
+        }
         if ((current.status === 'sending' && Number(current.claimUntil) > Number(now())) ||
             (['attention', 'authorization'].includes(current.status) &&
               replacement.status === current.status) ||

frontend/issue-sheet.js

@@ -200,7 +200,7 @@ function createIssueSheet({ fetchJson, storage, renderMarkdown = globalThis.rend
       container.classList.toggle('checklist-pending', detail.checklist_pending === true);
       container.innerHTML = renderMarkdown(
         detail.body || 'No description provided.', {
-          interactiveTasks: Boolean(interactive) && detail.checklist_pending !== true,
+          interactiveTasks: Boolean(interactive),
         }
       );
     },