[add] Dev Container configuration for auto CDE

.devcontainer/Dockerfile

@@ -0,0 +1,4 @@
+FROM mcr.microsoft.com/devcontainers/cpp:debian
+
+RUN curl -fsSL https://xmake.io/shget.text | bash
+ENV PATH="/root/.local/bin:${PATH}"

.devcontainer/devcontainer.json

@@ -0,0 +1,14 @@
+{
+  "name": "C++",
+  "build": { "dockerfile": "Dockerfile" },
+  "customizations": {
+    "vscode": {
+      "extensions": [
+        "tboox.xmake-vscode",
+        "ms-vscode.cpptools-extension-pack",
+        "redhat.vscode-yaml",
+        "GitHub.copilot"
+      ]
+    }
+  }
+}