v2.0.5 — Read feature (mobile zen reader on the relay)

Per-card opt-in push to the relay for distraction-free mobile reading.
Not tag-based: a real cards.read_push column so the reading state
stays independent of whatever tags the user organises by.

hyprcrd
- cards.read_push column (0/1, default 0) via Database migration.
- POST /api/cards + PATCH /api/cards/{id} accept read_push; save hook
  posts the card (title+body, encrypted) and referenced images
  to the relay's /api/read endpoint. First inline image is flagged
  as the hero. Toggle-off / DELETE wipes the remote copy.
- Detail-bar toggle button ("Read" → "On relay") with filled book
  icon + inverted accent background when active; outline book icon
  in the bottom meta row of the board card when read_push=1.

relay
- read_items + read_attachments tables, encrypted under the
  inter-tenant key like messages (dual-format envelope).
- Client API: POST /api/read, DELETE /api/read/{uid}, POST
  /api/read-attachments. Session API: GET /api/read (list),
  GET /api/read/{uid} (single decrypted), GET /api/read-attachments/
  {uid}/{filename} (serves decrypted image bytes).
- Payload size caps raised to 15MB (attachments) / 2MB (items).
- New nav tab + view: list with thumbnails, click opens a zen reader
  overlay. Reader caps article width at 680px, bumps type to 17px/1.7,
  renders a minimal markdown subset (headings, lists, code fences,
  blockquotes, links, inline images), rewrites uploads/ references
  to the session-authed image endpoint. Escape closes the reader.
- Mobile-first: wider touch targets, tighter padding at ≤640px.

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

public/js/modules/detail.js

@@ -570,10 +570,50 @@ function updateDoneButton(card) {
     if (label) label.textContent = isDone ? 'Undone' : 'Done';
 }
 
+function updateReadButton(card) {
+    const isOn = !!Number(card?.read_push || 0);
+    const btn = $('detail-read-toggle');
+    const icon = $('detail-read-icon');
+    const label = $('detail-read-label');
+    if (!btn) return;
+    // Off state reuses the neutral control-bar style; on state inverts
+    // (accent-filled tile with dark text) so "this card sits on the relay
+    // right now" is visually unmistakable, matching typical toggle UIs.
+    btn.classList.toggle('bg-t-accent', isOn);
+    btn.classList.toggle('border-t-accent', isOn);
+    btn.classList.toggle('text-t-bg', isOn);
+    btn.classList.toggle('text-t-muted', !isOn);
+    btn.classList.toggle('hover:border-t-accent', !isOn);
+    btn.classList.toggle('hover:text-t-accent', !isOn);
+    if (icon) icon.className = (isOn ? 'ph-fill ph-book-open' : 'ph ph-book-open') + ' text-sm';
+    if (label) label.textContent = isOn ? 'On relay' : 'Read';
+    btn.title = isOn
+        ? 'On relay — click to remove from your Read list'
+        : 'Push this card to your relay\'s Read list for distraction-free mobile reading';
+}
+
+$('detail-read-toggle')?.addEventListener('click', async () => {
+    const card = state.viewingCard;
+    if (!card) return;
+    const next = Number(card.read_push || 0) ? 0 : 1;
+    try {
+        const updated = await api(`api/cards/${card.id}`, { method: 'PATCH', body: { read_push: next } });
+        if (updated && !updated.error) {
+            card.read_push = updated.read_push;
+            card.relay_uid = updated.relay_uid;
+            const c = state.cards.find(x => x.id == card.id);
+            if (c) { c.read_push = updated.read_push; c.relay_uid = updated.relay_uid; }
+            updateReadButton(card);
+            window._renderBoard?.();
+        }
+    } catch (_) { /* network error: silently ignore */ }
+});
+
 function showContent(card) {
     $('detail-color').style.background = card.color;
     titleEl.textContent = card.title;
     updateDoneButton(card);
+    updateReadButton(card);
     const doneCorner = $('detail-done-corner');
     if (doneCorner) doneCorner.classList.toggle('hidden', !(card.tags || '').split(',').includes('done'));
     bodyEl.innerHTML = renderMd(card.body);