feat: Notion-style block editor v1 + Move to Trash + fixes

- Block editor: 13 block types with contentEditable + vanilla JS event delegation
- Slash menu /: 14 commands, 100% vanilla JS (zero Alpine conflicts)
- Keyboard: Enter=new block, Shift+Enter=soft break, arrows navigate blocks
- Drag & drop: SortableJS with 6-dot handles on block-wrapper
- Move to Trash: DELETE /board/api/pages/{id} + instant sidebar cleanup
- Placeholders: 'New page' + 'Type / for commands' in gray (CSS :empty::before)
- Redirect after delete stays in project context via workspaceKey
- Fixes: title auto-save, cursor positioning, x-for keys, Sortable guard

app/templates/base.html

@@ -389,6 +389,7 @@
       // ── Drag & drop tree ──
       treeSortables: [],
       initTreeSortable() {
+        if (typeof Sortable === 'undefined') return;
         // Initialize SortableJS on every .sidebar-items list
         const self = this;
         document.querySelectorAll('.sidebar-items').forEach(function(el) {
@@ -475,8 +476,29 @@
             alert(`Moved to ${section}`);
             break;
           case 'delete':
-            if (!confirm(`Delete "${pageName}"?`)) break;
-            alert('Delete not yet implemented (pages go to Trash in DB)');
+            if (!confirm(`Move "${pageName}" to trash?`)) break;
+            const delNum = pageId.replace('page/', '');
+            fetch(`/board/api/pages/${delNum}`, {
+              method: 'DELETE', headers: { 'X-CSRF-Token': csrf }
+            })
+            .then(r => { if (!r.ok) throw new Error('Delete failed'); return r.json(); })
+            .then(data => {
+              // Remove from ALL sidebar sections (Recents, Private, etc.)
+              const items = document.querySelectorAll(`.sidebar-item[data-page-id="${pageId}"]`);
+              items.forEach(item => {
+                const next = item.nextElementSibling;
+                if (next && next.classList.contains('tree-children-wrapper')) {
+                  next.remove();
+                }
+                item.remove();
+              });
+              // Redirect if viewing deleted page — stay in project context
+              if (window.location.pathname.includes(`/pages/${delNum}`)) {
+                const wk = this.workspaceKey;
+                window.location.href = wk && wk.includes('/') ? `/board/${wk}` : '/';
+              }
+            })
+            .catch(e => alert('Delete failed: ' + e.message));
             break;
           case 'openTab':
             window.open('/' + pageId, '_blank');
@@ -501,7 +523,7 @@
       },
       newPage(section) {
         const project = this.workspaceKey || '';
-        fetch(`/board/api/pages?title=New%20page&section=${encodeURIComponent(section)}&project=${encodeURIComponent(project)}`, {
+        fetch(`/board/api/pages?section=${encodeURIComponent(section)}&project=${encodeURIComponent(project)}`, {
           method: 'POST',
           headers: { 'X-CSRF-Token': this.getCsrfToken() }
         })
@@ -512,7 +534,7 @@
       newSubPage(parentId) {
         const project = this.workspaceKey || '';
         const pid = parentId.replace('page/', '');
-        fetch(`/board/api/pages?title=New%20sub-page&section=Private&project=${encodeURIComponent(project)}&parent_id=${pid}`, {
+        fetch(`/board/api/pages?section=Private&project=${encodeURIComponent(project)}&parent_id=${pid}`, {
           method: 'POST',
           headers: { 'X-CSRF-Token': this.getCsrfToken() }
         })