feat(generator): add jQuery + fetch dual HTTP client support in template

Enhance defaultDeps with:
- validatePageContext: Checks hostname against expected_domain for page context validation
- queryData: Dual HTTP client with jQuery $.ajax as primary and fetch as fallback
  - jQuery preferred for internal pages that typically have it
  - Clear error message if neither client is available

🤖 Generated with [Qoder][https://qoder.com]

src/generated_scene/generator.rs

@@ -347,18 +347,51 @@ function buildArtifact(args, rows) {{
 }}
 
 const defaultDeps = {{
-  validatePageContext: async () => true,
-  queryData: async (args) => {{
+  validatePageContext(args) {{
+    const host = (globalThis.location?.hostname || '').trim();
+    const expected = (args.expected_domain || '').trim();
+    if (!host) return {{ ok: false, reason: 'page_context_unavailable' }};
+    if (host !== expected) return {{ ok: false, reason: 'page_context_mismatch' }};
+    return {{ ok: true }};
+  }},
+
+  async queryData(args) {{
     const endpoint = API_ENDPOINTS[0];
     if (!endpoint) throw new Error('No API endpoint configured');
     const request = buildRequest(args, endpoint);
-    const response = await fetch(request.url, {{
-      method: request.method,
-      headers: request.headers,
-      body: request.body
-    }});
-    if (!response.ok) throw new Error(`HTTP ${{response.status}}: ${{response.statusText}}`);
-    return response.json();
+
+    // Prefer jQuery (internal pages typically have it)
+    if (typeof $ !== 'undefined' && typeof $.ajax === 'function') {{
+      return new Promise((resolve, reject) => {{
+        $.ajax({{
+          url: request.url,
+          type: request.method,
+          data: request.body,
+          contentType: 'application/json',
+          dataType: 'json',
+          success: resolve,
+          error: (xhr, status, err) => reject(new Error(
+            `API failed (${{xhr.status}}): ${{err}} | body=${{(xhr.responseText || '').substring(0, 200)}}`
+          ))
+        }});
+      }});
+    }}
+
+    // Fallback: fetch API
+    if (typeof fetch === 'function') {{
+      const response = await fetch(request.url, {{
+        method: request.method,
+        headers: request.headers,
+        body: request.method !== 'GET' ? request.body : undefined
+      }});
+      if (!response.ok) {{
+        const text = await response.text().catch(() => '');
+        throw new Error(`HTTP ${{response.status}}: ${{text.substring(0, 200)}}`);
+      }}
+      return response.json();
+    }}
+
+    throw new Error('No HTTP client available (need jQuery or fetch)');
   }}
 }};