fix: add simple devcontainer

.devcontainer/Dockerfile

@@ -0,0 +1 @@
+FROM node:20

.devcontainer/devcontainer.json

@@ -0,0 +1,11 @@
+{
+	"name": "SAFE",
+	"dockerFile": "Dockerfile",
+	"appPort": [8080, 8085],
+	"extensions": [
+		"ionide.ionide-fsharp",
+        "ms-dotnettools.csharp",
+        "editorconfig.editorconfig",
+        "msjsdiag.debugger-for-chrome"
+	]
+}

.devcontainer/settings.vscode.json

@@ -0,0 +1,3 @@
+{
+    "FSharp.fsacRuntime":"netcore"
+}