feat(viewer): group-by-project toggle + Gitea 404 handling

- static/board.js: full rerender on toggle-grouping; by-project mode = N cols
  per project with status-badge inside cards, sorted by canonical status order
- static/board.css: drop placeholder, add .badge.status
- src/gitea.ts: getLatestCommitIso returns null on 404 (path never existed
  remotely; seen on books repo where some per-task slugs in STATUS.md
  don't have file in default branch) + new test
- .gitignore: dist/ already present; add .playwright-mcp/, board-*.png

Smoke-verified: dist/index.html, 78 records from 4 repos, both toggle modes
work in browser, drawer lazy-fetches markdown.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

static/board.css

@@ -242,16 +242,6 @@ aside.drawer[hidden] {
   padding: 0;
 }
 
-body.group-by-project main.board {
-  grid-template-columns: 1fr;
-}
-
-body.group-by-project main.board .col {
-  display: none;
-}
-
-body.group-by-project main.board::after {
-  content: "grouping by project: not implemented yet";
-  color: var(--muted);
-  padding: 1rem;
+.badge.status {
+  background: var(--badge-bg);
 }

static/board.js

@@ -11,10 +11,116 @@ const drawerContent = drawer?.querySelector('.drawer-content');
 const drawerClose = drawer?.querySelector('.drawer-close');
 const refreshInfo = document.querySelector('.refresh-info');
 const header = document.querySelector('header');
+const board = document.querySelector('main.board');
 
 const generatedAt = header?.dataset.generated ? new Date(header.dataset.generated) : null;
 const NEXT_TICK_MIN = 5;
 
+const STATUS_ORDER = ['open', 'in_progress', 'paused', 'blocked', 'done'];
+const STATUS_LABEL = {
+  open: 'open',
+  in_progress: 'in-progress',
+  paused: 'paused',
+  blocked: 'blocked',
+  done: 'done',
+};
+const STATUS_EMOJI = {
+  open: '⚪',
+  in_progress: '🔴',
+  paused: '🟡',
+  blocked: '🔵',
+  done: '🟢',
+};
+
+const ARCHIVE_DAYS = 14;
+
+function escapeHtml(s) {
+  return String(s)
+    .replace(/&/g, '&')
+    .replace(/</g, '&lt;')
+    .replace(/>/g, '&gt;')
+    .replace(/"/g, '&quot;')
+    .replace(/'/g, '&#39;');
+}
+
+function formatAge(iso, now) {
+  if (!iso) return null;
+  const then = new Date(iso);
+  const diff = Math.max(0, now.getTime() - then.getTime());
+  const m = Math.floor(diff / 60_000);
+  if (m < 60) return `${m}m`;
+  const h = Math.floor(diff / 3_600_000);
+  if (h < 24) return `${h}h`;
+  const d = Math.floor(diff / 86_400_000);
+  if (d < 7) return `${d}d`;
+  if (d < 30) return `${Math.floor(d / 7)}w`;
+  let mo =
+    (now.getUTCFullYear() - then.getUTCFullYear()) * 12 +
+    (now.getUTCMonth() - then.getUTCMonth());
+  if (now.getUTCDate() < then.getUTCDate()) mo -= 1;
+  mo = Math.max(0, mo);
+  if (mo < 12) return `${mo}mo`;
+  return `${Math.floor(mo / 12)}y`;
+}
+
+function isArchived(rec, now) {
+  if (rec.status !== 'done' || !rec.last_commit_iso) return false;
+  const ms = now.getTime() - new Date(rec.last_commit_iso).getTime();
+  return ms > ARCHIVE_DAYS * 86_400_000;
+}
+
+function truncate(s, max) {
+  return s.length <= max ? s : s.slice(0, max) + '…';
+}
+
+function renderCard(rec, now, mode) {
+  const age = formatAge(rec.last_commit_iso, now);
+  const archived = isArchived(rec, now);
+  const meta = mode === 'by-project'
+    ? `<span class="badge status">${STATUS_EMOJI[rec.status]} ${STATUS_LABEL[rec.status]}</span>`
+    : `<span class="badge project">${escapeHtml(rec.project)}</span>`;
+  return `<li class="card" data-slug="${escapeHtml(rec.slug)}" data-raw-url="${escapeHtml(rec.raw_url)}" data-archived="${archived ? 'true' : 'false'}">
+    <div class="card-title">${escapeHtml(truncate(rec.title, 80))}</div>
+    <div class="card-meta">
+      ${meta}
+      ${age === null ? '' : `<span class="age">${escapeHtml(age)}</span>`}
+    </div>
+  </li>`;
+}
+
+function renderByStatus(now) {
+  return STATUS_ORDER.map((status) => {
+    const inCol = records.filter((r) => r.status === status);
+    const cards = inCol.map((r) => renderCard(r, now, 'by-status')).join('');
+    return `<section class="col" data-status="${status}">
+      <h2>${STATUS_EMOJI[status]} ${STATUS_LABEL[status]} <span class="count">${inCol.length}</span></h2>
+      <ul class="cards">${cards}</ul>
+    </section>`;
+  }).join('');
+}
+
+function renderByProject(now) {
+  const projects = [...new Set(records.map((r) => r.project))].sort();
+  return projects.map((project) => {
+    const inCol = records
+      .filter((r) => r.project === project)
+      .sort((a, b) => STATUS_ORDER.indexOf(a.status) - STATUS_ORDER.indexOf(b.status));
+    const cards = inCol.map((r) => renderCard(r, now, 'by-project')).join('');
+    return `<section class="col" data-project="${escapeHtml(project)}">
+      <h2>${escapeHtml(project)} <span class="count">${inCol.length}</span></h2>
+      <ul class="cards">${cards}</ul>
+    </section>`;
+  }).join('');
+}
+
+function rerender() {
+  if (!board) return;
+  const now = new Date();
+  const byProject = toggleGrouping?.checked;
+  board.innerHTML = byProject ? renderByProject(now) : renderByStatus(now);
+  if (filterInput) applyFilter(filterInput.value);
+}
+
 function relativeMin(ms) {
   return Math.max(0, Math.floor(ms / 60000));
 }
@@ -33,8 +139,9 @@ function applyFilter(query) {
   document.querySelectorAll('.card').forEach((card) => {
     const slug = card.dataset.slug || '';
     const project = card.querySelector('.badge.project')?.textContent || '';
+    const status = card.querySelector('.badge.status')?.textContent || '';
     const title = card.querySelector('.card-title')?.textContent || '';
-    const hay = `${slug} ${project} ${title}`.toLowerCase();
+    const hay = `${slug} ${project} ${status} ${title}`.toLowerCase();
     card.dataset.hidden = q === '' || hay.includes(q) ? 'false' : 'true';
   });
 }
@@ -47,8 +154,9 @@ toggleArchived?.addEventListener('change', (e) => {
   document.body.classList.toggle('show-archived', e.target.checked);
 });
 
-toggleGrouping?.addEventListener('change', (e) => {
-  document.body.classList.toggle('group-by-project', e.target.checked);
+toggleGrouping?.addEventListener('change', () => {
+  document.body.classList.toggle('group-by-project', toggleGrouping.checked);
+  rerender();
 });
 
 async function openDrawer(card) {
@@ -56,7 +164,7 @@ async function openDrawer(card) {
   const rawUrl = card.dataset.rawUrl;
   const slug = card.dataset.slug;
   if (!rawUrl) return;
-  drawerContent.innerHTML = `<h2>${slug}</h2><p>loading…</p>`;
+  drawerContent.innerHTML = `<h2>${escapeHtml(slug || '')}</h2><p>loading…</p>`;
   drawer.hidden = false;
   try {
     const res = await fetch(rawUrl, { credentials: 'omit' });
@@ -81,13 +189,4 @@ document.addEventListener('keydown', (e) => {
   if (e.key === 'Escape' && drawer) drawer.hidden = true;
 });
 
-function escapeHtml(s) {
-  return s
-    .replace(/&/g, '&amp;')
-    .replace(/</g, '&lt;')
-    .replace(/>/g, '&gt;')
-    .replace(/"/g, '&quot;')
-    .replace(/'/g, '&#39;');
-}
-
 console.log(`board-viewer: ${records.length} records loaded`);