Single-object viewer POC (#14)

This commit implements a Sketchfab-style single-object viewer as a minimal
proof-of-concept.

### `@storyteller/studio-web`
This is a new package to house web components for interfacing with the
`@storyteller/studio` WASM library. It currently includes a single component,
`<sts-viewer />`, which is exported from `@storyteller/studio-web/viewer`.

### `react-frontend`
This is a new application intended as a proof-of-concept and testbed for React
interop with `@storyteller/studio-web`.

Web components are currently a little bit fiddly to use in a React application.
`react-frontend/src/app/studio-viewer.tsx` demonstrates how a React-idiomatic
component can be written as a thin wrapper around a web component, and
`react-frontend/src/app/app.tsx` demonstrates that wrapper component in use.

studio-web/tsconfig.json

@@ -0,0 +1,22 @@
+{
+  "extends": "../tsconfig.base.json",
+  "compilerOptions": {
+    "module": "commonjs",
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "noImplicitOverride": true,
+    "noPropertyAccessFromIndexSignature": true,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": true
+  },
+  "files": [],
+  "include": [],
+  "references": [
+    {
+      "path": "./tsconfig.lib.json"
+    },
+    {
+      "path": "./tsconfig.spec.json"
+    }
+  ]
+}