fix: update preview response parsing for PR #185 schema clarifications

PR #185 in adcp/adcp clarified the preview response structure:
- preview_url and preview_html are now in renders[0], not directly on preview
- Added preview_id and render_id fields for better identification
- Updated both single-mode and batch-mode parsing to match new structure
- Updated test mocks to reflect new schema structure

All 106 tests passing ✅

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: bokelley

src/adcp/utils/preview_cache.py

@@ -80,15 +80,18 @@ async def get_preview_data_for_manifest(
 
             if result.success and result.data and result.data.previews:
                 preview = result.data.previews[0]
+                renders = preview.get("renders", [])
+                first_render = renders[0] if renders else {}
+
                 preview_data = {
-                    "preview_url": preview.get("preview_url"),
+                    "preview_id": preview.get("preview_id"),
+                    "preview_url": first_render.get("preview_url"),
+                    "preview_html": first_render.get("preview_html"),
+                    "render_id": first_render.get("render_id"),
                     "input": preview.get("input", {}),
                     "expires_at": result.data.expires_at,
                 }
 
-                if preview.get("renders"):
-                    preview_data["renders"] = preview["renders"]
-
                 self._preview_cache[cache_key] = preview_data
                 return preview_data
 
@@ -174,19 +177,13 @@ async def get_preview_data_batch(
                             response = batch_result["response"]
                             if response.get("previews"):
                                 preview = response["previews"][0]
-                                renders = preview.get("renders", [{}])
+                                renders = preview.get("renders", [])
                                 first_render = renders[0] if renders else {}
                                 preview_data = {
-                                    "preview_url": (
-                                        first_render.get("preview_url")
-                                        if preview.get("renders")
-                                        else None
-                                    ),
-                                    "preview_html": (
-                                        first_render.get("preview_html")
-                                        if preview.get("renders")
-                                        else None
-                                    ),
+                                    "preview_id": preview.get("preview_id"),
+                                    "preview_url": first_render.get("preview_url"),
+                                    "preview_html": first_render.get("preview_html"),
+                                    "render_id": first_render.get("render_id"),
                                     "input": preview.get("input", {}),
                                     "expires_at": response.get("expires_at"),
                                 }

tests/test_preview_html.py

@@ -105,7 +105,17 @@ async def test_get_preview_data_for_manifest():
     # Parsed result from _parse_response
     mock_preview_response = PreviewCreativeResponse(
         previews=[
-            {"preview_url": "https://preview.example.com/abc123", "input": {"name": "Desktop"}}
+            {
+                "preview_id": "preview-1",
+                "renders": [
+                    {
+                        "render_id": "render-1",
+                        "preview_url": "https://preview.example.com/abc123",
+                        "preview_html": None,
+                    }
+                ],
+                "input": {"name": "Desktop"},
+            }
         ],
         expires_at="2025-12-01T00:00:00Z",
     )