docs: add demo video URL, update blog count to 18, fix post URLs

Author: ComBba

README.md

@@ -17,6 +17,10 @@
   <img src="https://img.shields.io/badge/GCP-Cloud_Run-4285F4?style=flat-square&logo=googlecloud&logoColor=white" alt="GCP">
 </p>
 
+<p align="center">
+  <a href="https://youtu.be/csR-gjEoWp8">▶ Watch the 4-minute demo video</a>
+</p>
+
 ---
 
 ## The Problem
@@ -562,10 +566,11 @@ These feed Cloud Logging, Cloud Trace, and Cloud Monitoring. Completed task repl
 
 ### Dev.to Blog Posts
 
-15 published articles documenting the development journey:
+18 published articles documenting the development journey:
 
-- [the moment vibecat stopped waiting and started suggesting](https://dev.to/combba/the-moment-vibecat-stopped-waiting-and-started-suggesting-4ek) — Proactive Companion pivot
-- [six characters, one soul](https://dev.to/combba/six-characters-one-soul-5008) — Character system architecture
+- [submitting vibecat: what 3 weeks of building a desktop AI actually taught me](https://dev.to/combba/submitting-vibecat-what-3-weeks-of-building-a-desktop-ai-actually-taught-me-1409) — Submission day retrospective (series finale)
+- [when your agent fails, does it just... stop?](https://dev.to/combba/when-your-agent-fails-does-it-just-stop-5c77) — Self-healing deep dive
+- [the moment vibecat stopped waiting and started suggesting](https://dev.to/combba/the-moment-vibecat-stopped-waiting-and-started-suggesting-5ba9) — Proactive Companion pivot
 - Full series: [dev.to/combba](https://dev.to/combba)
 
 ## License

docs/challenge/video-1-demo/SCRIPT.md

@@ -197,7 +197,7 @@ Pattern: VibeCat always observes → describes what it sees → asks permission.
 | **Innovation & Multimodal UX (40%)** | Voice-first, proactive AI that speaks before asked. Triple-source grounding (AX+CDP+Vision). No text boxes. |
 | **Technical Implementation (30%)** | GenAI SDK + ADK on Cloud Run. 5 FC tools. Self-healing with vision verification. |
 | **Demo & Presentation (30%)** | Real working software. Architecture diagram. GCP Console proof. Clear problem→solution narrative. |
-| **Blog Bonus (+0.6)** | 15 posts on dev.to/combba |
+| **Blog Bonus (+0.6)** | 18 posts on dev.to/combba |
 | **Auto Deploy (+0.2)** | infra/deploy.sh |
 | **GDG (+0.2)** | gdg.community.dev/u/m5n58q/ |