feat: convert Deployment to Rollout CRD with canary strategy

- Replace deployment.yaml with rollout.yaml
- Add canary-service.yaml for traffic splitting
- Add analysistemplate.yaml for Prometheus health checks
- Update HTTPRoute with dual backends (stable + canary)
- Update overlays with Rollout patches
- Add Rollout transformer configuration for Kustomize

apps/myapp/base/rollout.yaml

@@ -0,0 +1,47 @@
+apiVersion: argoproj.io/v1alpha1
+kind: Rollout
+metadata:
+  name: myapp
+  labels:
+    app: myapp
+    managed-by: argocd
+spec:
+  revisionHistoryLimit: 3
+  selector:
+    matchLabels:
+      app: myapp
+  strategy:
+    canary:
+      canaryService: myapp-canary
+      stableService: myapp
+      trafficRouting:
+        plugins:
+          argoproj-labs/gatewayAPI:
+            httpRoute: myapp-route
+            namespace: default
+      analysis:
+        templates:
+        - templateName: success-rate
+        args:
+        - name: service-name
+          value: myapp
+        startingStep: 1
+      steps:
+      - setWeight: 10
+      - pause: {duration: 30s}
+      - setWeight: 30
+      - pause: {duration: 1m}
+      - setWeight: 60
+      - pause: {duration: 1m}
+      - setWeight: 100
+  template:
+    metadata:
+      labels:
+        app: myapp
+    spec:
+      containers:
+      - name: myapp
+        image: nginx:alpine
+        ports:
+        - name: http
+          containerPort: 80