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.

package.json

@@ -13,6 +13,7 @@
     "@swc/core": "~1.3.85",
     "@types/lodash": "^4.14.199",
     "@types/node": "18.7.1",
+    "@vitest/coverage-c8": "~0.32.0",
     "@vitest/ui": "~0.32.0",
     "chalk": "^5.3.0",
     "glob": "^10.3.10",
@@ -23,12 +24,14 @@
     "swc-loader": "0.1.15",
     "typescript": "~5.1.3",
     "vite": "~4.3.9",
+    "vite-plugin-dts": "~2.3.0",
     "vite-plugin-top-level-await": "^1.3.1",
     "vite-plugin-wasm": "^3.2.2",
     "vitest": "~0.32.0",
     "wasm-pack": "^0.12.1"
   },
   "dependencies": {
+    "lit": "^2.8.0",
     "lodash": "^4.17.21",
     "tslib": "^2.3.0"
   }