Fix embedded bridge and adapt to changes in core code:
- Add `EmbeddedBridgeSettings` so it can be used in settings.
- Add `AIOBridge` and `TwistedBridge` wrappers.
- Fix callbacks, instead of logging them (and breaking the errback chain), they are now
raised using `BridgeException` like in other bridges.
- Ensure that a singleton `Bridge` is used between backend and frontend.
- Init backend on first call to `bridge_connect`.
- Add Python 3.14 fix (as it is normally done in Launcher which is not run with with
`embedded`, we have to do it there).
- Track generated files.
a722464238