Crude first pass at playground page

playground/src/global.d.ts

@@ -0,0 +1,13 @@
+export {}
+declare global {
+  interface Process {
+    stdout: {
+      write(s: string): void
+    },
+    argv: string[]
+
+  }
+  let files : Record<string,string>
+  let process : Process
+  let __mainExpression_0 : () => unknown
+}