Function createDefaultBridges

createDefaultBridges(options?: DefaultBridgesOptions): BridgeRegistry
The shell's bridge registry: the web bridge, complete, plus the downloads, sharing and mail bridges. With a handoff opener those four hand each locator to an app on the user's device; without one they report unavailable (D-010). A torrent backend replaces the hand-off for magnet links, so they download inside kernl (D-017).
Parameters
- options: DefaultBridgesOptions = {}
  Consent hook, outcome observer, web bridge options, the hand-off opener and the torrent backend.
Returns BridgeRegistry
A BridgeRegistry.
Example
```
createDefaultBridges().forScheme('magnet')?.availability(); // { available: false, reason: 'no-backend' }
const bridges = createDefaultBridges({ handoff: (uri) => host.openLink(uri) });
bridges.forScheme('magnet')?.availability(); // { available: true, handoff: true }
const inKernl = createDefaultBridges({ handoff, torrent: createWebTorrentBackend({ client }) });
inKernl.forScheme('magnet')?.availability(); // { available: true }
```