fix: default image tag to latest — 2.0.0-dev was stale

The 2.0.0-dev tag was only built from the now-merged
feature/serverless-2.0.0 branch. Pushes to main only tagged latest,
so the 2.0.0-dev image in the registry was frozen and missing all
recent fixes. Default to latest and also tag main builds as 2.0.0-dev
for backwards compatibility.

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

chart/values.yaml

@@ -13,7 +13,7 @@ deploymentMode: persistent  # persistent | dynamic
 # Container image configuration
 image:
   repository: ghcr.io/cpfarhood/devcontainer
-  tag: 2.0.0-dev
+  tag: latest
   pullPolicy: Always
 
 # GitHub repository to clone into /workspace (ignored in dynamic mode - uses URL routing)
@@ -217,7 +217,7 @@ dynamic:
     replicas: 2                    # High availability
     image:
       repository: ghcr.io/cpfarhood/devcontainer-routing-proxy
-      tag: 2.0.0-dev
+      tag: latest
       pullPolicy: Always
 
     resources: