Add dev container for Codespaces support (#27)

* Add devcontainer for Codespaces

* Simplify the devcontainer

Author: pamelafox

.devcontainer/devcontainer.json

@@ -0,0 +1,18 @@
+{
+    "name": "The Claude on Foundry Starter Kit",
+    "image": "mcr.microsoft.com/devcontainers/python:3.13-bookworm",
+    "features": {
+        "ghcr.io/devcontainers/features/azure-cli:1.2.5": {},
+        "ghcr.io/azure/azure-dev/azd:latest": {}
+    },
+    "customizations": {
+        "vscode": {
+            "extensions": [
+                "ms-azuretools.azure-dev",
+                "ms-azuretools.vscode-bicep",
+                "ms-python.python"
+            ]
+        }
+    },
+    "remoteUser": "vscode"
+}