fix: replace unsupported journey diagrams with flowcharts in README

The 'journey' mermaid type fails to render on GitHub and most viewers.
Replaced both Feature Delivery and Incident Response journey diagrams
with equivalent flowchart LR diagrams with colour-coded subgraphs.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: JeevantheDev

README.md

@@ -678,49 +678,63 @@ sequenceDiagram
 ### Feature Delivery Journey
 
 ```mermaid
-journey
-    title Feature Delivery Journey
-    section Planning
-      Paste ticket into ShipBrain: 5: Engineer
-      Review AI task decomposition: 4: Engineer
-      Edit tasks if needed: 3: Engineer
-    section Development
-      Approve Draft PR creation: 5: Engineer
-      Work on PR locally: 3: Engineer
-      Push changes, CI runs: 4: Engineer
-    section Preview
-      Merge PR to develop: 5: Engineer
-      Preview auto-deploys: 5: System
-      QA validates preview: 4: QA
-    section Production
-      Create release PR: 5: Engineer
-      Manager approves deployment: 5: Manager
-      Production deploys: 5: System
-      Monitor for issues: 3: Engineer
+flowchart LR
+    subgraph Planning
+        A([📋 Paste ticket]) --> B([🤖 AI decomposes tasks])
+        B --> C([✏️ Engineer reviews & edits])
+    end
+    subgraph Development
+        C --> D([✅ Approve Draft PR])
+        D --> E([💻 Work on PR locally])
+        E --> F([🔄 Push — CI runs])
+    end
+    subgraph Preview
+        F --> G([🔀 Merge PR to develop])
+        G --> H([🚀 Preview auto-deploys])
+        H --> I([🔍 QA validates preview])
+    end
+    subgraph Production
+        I --> J([📦 Create release PR])
+        J --> K([✅ Manager approves])
+        K --> L([🌐 Production deploys])
+        L --> M([📊 Monitor for issues])
+    end
+
+    style Planning fill:#1e3a5f,color:#fff,stroke:#1e3a5f
+    style Development fill:#1a3a2a,color:#fff,stroke:#1a3a2a
+    style Preview fill:#3a2a00,color:#fff,stroke:#3a2a00
+    style Production fill:#3a1a5f,color:#fff,stroke:#3a1a5f
 ```
 
 ### Incident Response Journey
 
 ```mermaid
-journey
-    title Incident Response Journey
-    section Detection
-      Alert fires from monitoring: 2: System
-      ShipBrain ingests alert: 5: System
-      Team notified via Telegram: 5: System
-    section Analysis
-      AI analyzes root cause: 5: System
-      Fix proposal generated: 5: System
-      Engineer reviews analysis: 4: Engineer
-    section Resolution
-      Create hotfix branch: 5: Engineer
-      Approve hotfix deployment: 5: Manager
-      Hotfix deploys to production: 5: System
-      Reverse sync to develop: 5: System
-    section Post-Incident
-      Post-mortem auto-generated: 5: System
-      Team reviews post-mortem: 4: Team
-      Action items tracked: 4: Manager
+flowchart LR
+    subgraph Detection
+        A([🚨 Alert fires]) --> B([📥 ShipBrain ingests])
+        B --> C([📱 Telegram notified])
+    end
+    subgraph Analysis
+        C --> D([🤖 AI root-cause analysis])
+        D --> E([💡 Fix proposal generated])
+        E --> F([👀 Engineer reviews])
+    end
+    subgraph Resolution
+        F --> G([🔧 Create hotfix branch])
+        G --> H([✅ Manager approves])
+        H --> I([🚀 Hotfix deploys])
+        I --> J([🔁 Reverse sync → develop])
+    end
+    subgraph Post-Incident
+        J --> K([📄 Post-mortem generated])
+        K --> L([👥 Team reviews])
+        L --> M([✅ Incident resolved])
+    end
+
+    style Detection fill:#5f1a1a,color:#fff,stroke:#5f1a1a
+    style Analysis fill:#1e3a5f,color:#fff,stroke:#1e3a5f
+    style Resolution fill:#1a3a2a,color:#fff,stroke:#1a3a2a
+    style Post-Incident fill:#2a2a2a,color:#fff,stroke:#2a2a2a
 ```
 
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