fix: use native installer for Claude Code instead of npm

The recommended installation method for Claude Code is now the native
installer script, which also provides automatic background updates.

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

Author: dstengle

.devcontainer/devcontainer.json

@@ -52,7 +52,7 @@
 	//  "runArgs" : [
 	// 		"--network="
 	//  ]
-	"postCreateCommand": "npm install -g @anthropic-ai/claude-code",
+	"postCreateCommand": "curl -fsSL https://claude.ai/install.sh | bash",
 
 	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
 	// "remoteUser": "root"