[🐛] Missing firebase-js-sdk API

## Issue

**Unimplemented JS SDK features include:**
- [ ] **storage.uploadBytes** (~~This one is a blocker for us~~) `uploadBytesResumable` seems like a drop-in replacement, at least for us, but maybe not for everyone and probably is a bit heavier to run. Ideally `uploadBytes` would be supported still. _(Update: This may produce intermittent issues not seen with uploadBytes, or it might be a coincidence)_
- [ ] storage.getStream
- [ ] storage.getBlob
- [ ] storage.getBytesSync
- [ ] database.forceLongPolling
- [ ] database.forceWebSockets
- [x] **auth.TotpMultiFactorGenerator (Required for authenticator-app-based multifactor)**

**Also possibly the following:**
- [x] auth.unenroll
- [x] auth.addTokenListener

I located these by searching for the string `not implemented` in the portions of the project we use. I've also made an effort to document the others but this may not be comprehensive, or may contain false positives for the `auth` ones.

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