chore: add recommended VS Code extensions

Ruff, Python, mypy, debugpy, Even Better TOML, EditorConfig, and
GitHub Copilot.

Author: KRRT7

.vscode/extensions.json

@@ -0,0 +1,11 @@
+{
+  "recommendations": [
+    "charliermarsh.ruff",
+    "ms-python.python",
+    "ms-python.mypy-type-checker",
+    "ms-python.debugpy",
+    "tamasfe.even-better-toml",
+    "EditorConfig.EditorConfig",
+    "github.copilot"
+  ]
+}