fix(docs): restore lockMode in demo — feature is published

lockMode is available in superdoc@latest (v1.13.1). Restore
sdtLocked on onReady field insertions and lock/unlock buttons.

Author: tupizz

apps/docs/snippets/extensions/structured-content.mdx

@@ -16,7 +16,7 @@ import { SuperDocEditor } from '/snippets/components/superdoc-editor.jsx'
     const editor = superdoc?.activeEditor || superdoc?.editor
     if (!editor?.commands) return
 
-    // Find "________" in "Client name:" paragraph and replace with inline field
+    // Find "________" in "Client name:" paragraph and replace with inline sdtLocked field
     let inlinePos = null
     editor.state.doc.descendants((node, pos) => {
       if (node.isText && node.text.includes('________') && inlinePos === null) {
@@ -26,12 +26,12 @@ import { SuperDocEditor } from '/snippets/components/superdoc-editor.jsx'
     if (inlinePos !== null) {
       editor.commands.setTextSelection({ from: inlinePos, to: inlinePos + 8 })
       editor.commands.insertStructuredContentInline({
-        attrs: { id: '1', alias: 'Client Name' },
+        attrs: { id: '1', alias: 'Client Name', lockMode: 'sdtLocked' },
         text: 'John Doe',
       })
     }
 
-    // Find the second "________" paragraph and replace with block field
+    // Find the second "________" paragraph and replace with block sdtLocked field
     let blockPos = null
     editor.state.doc.descendants((node, pos) => {
       if (node.isText && node.text.includes('________')) {
@@ -41,7 +41,7 @@ import { SuperDocEditor } from '/snippets/components/superdoc-editor.jsx'
     if (blockPos !== null) {
       editor.commands.setTextSelection({ from: blockPos, to: blockPos + 8 })
       editor.commands.insertStructuredContentBlock({
-        attrs: { id: '2', alias: 'Payment Terms' },
+        attrs: { id: '2', alias: 'Payment Terms', lockMode: 'sdtLocked' },
         json: { type: 'paragraph', content: [{ type: 'text', text: 'Payment is due within 30 days of invoice date. Late payments incur a 1.5% monthly fee.' }] },
       })
     }
@@ -67,6 +67,37 @@ import { SuperDocEditor } from '/snippets/components/superdoc-editor.jsx'
         }
       },
     ],
+    [
+      {
+        label: 'Lock inline (sdtContentLocked)',
+        onClick: (superdoc) => {
+          const editor = superdoc?.activeEditor || superdoc?.editor
+          if (!editor?.commands) return
+          editor.commands.updateStructuredContentById('1', {
+            attrs: { lockMode: 'sdtContentLocked' },
+          });
+        }
+      },
+      {
+        label: 'Lock block (sdtContentLocked)',
+        onClick: (superdoc) => {
+          const editor = superdoc?.activeEditor || superdoc?.editor
+          if (!editor?.commands) return
+          editor.commands.updateStructuredContentById('2', {
+            attrs: { lockMode: 'sdtContentLocked' },
+          });
+        }
+      },
+      {
+        label: 'Unlock all',
+        onClick: (superdoc) => {
+          const editor = superdoc?.activeEditor || superdoc?.editor
+          if (!editor?.commands) return
+          editor.commands.updateStructuredContentById('1', { attrs: { lockMode: 'unlocked' } });
+          editor.commands.updateStructuredContentById('2', { attrs: { lockMode: 'unlocked' } });
+        }
+      },
+    ],
     [
       {
         label: 'Delete all fields',