Integrate QOI codec completely

* Adds code for encoders and decoders
* Cleans up some obsolete QOI-related code

src/client/lazy-app/Compress/index.tsx

@@ -111,6 +111,9 @@ async function decodeImage(
       if (mimeType === 'image/webp2') {
         return await workerBridge.wp2Decode(signal, blob);
       }
+      if (mimeType === 'image/qoi') {
+        return await workerBridge.qoiDecode(signal, blob);
+      }
     }
     // Otherwise fall through and try built-in decoding for a laugh.
     return await builtinDecode(signal, blob);