chore: bump chart version to 0.1.15

Triggers OCI artifact rebuild so Flux picks up the MCP sidecar changes.

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

chart/Chart.yaml

@@ -2,5 +2,5 @@ apiVersion: v2
 name: devcontainer
 description: Antigravity Dev Container with Happy Coder AI assistant
 type: application
-version: 0.1.14
+version: 0.1.15
 appVersion: "latest"