UI infrastructure and simple "Help" dialog (#3)

Sets up some WIP infrastructure for building out the UI, and adds a simple popup
to show the navigation controls for the app.

framework/tsconfig.lib.json

@@ -0,0 +1,10 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "outDir": "../dist/out-tsc",
+    "declaration": true,
+    "types": ["node", "vite/client"]
+  },
+  "include": ["src/**/*.ts"],
+  "exclude": ["jest.config.ts", "src/**/*.spec.ts", "src/**/*.test.ts"]
+}