feat: add asset preferences, video research, and Remotion ad assets

- Add thumbs-down feedback modal and preference API endpoint
- Add AI UGC video platforms research doc
- Add ReflectAd Remotion composition with public flow assets
- Add gemini-ad-designer and poster-ad-designer pipeline skills
- Add research_reflect_v1.1 pipeline script

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

pipeline/.claude/settings.local.json

@@ -0,0 +1,14 @@
+{
+  "permissions": {
+    "allow": [
+      "mcp__nanobanana__generate_image",
+      "mcp__nanobanana__gemini_generate_image",
+      "mcp__nanobanana__(.*)",
+      "Bash(*)",
+      "Read(*)",
+      "Write(*)",
+      "Grep(*)",
+      "Glob(*)"
+    ]
+  }
+}