This PR fixes an issue where the `zed-extension` CLI could no longer be
run as a static binary due to the following error:
```
dyld[36964]: Library not loaded: @rpath/WebRTC.framework/WebRTC
Referenced from: <56332E1D-292E-3F9B-97B9-8A9962D21599> /Users/maxdeviant/projects/zed-extensions/zed-extension
Reason: no LC_RPATH's found
fish: Job 1, './zed-extension --scratch-dir .…' terminated by signal SIGABRT (Abort)
```
This is the result of the addition of a dependency on `workspace` to the
`extension` crate (and thus, the `extension_cli` crate) in #12360.
Since we don't actually _need_ WebRTC in the extension CLI, we don't
care about dynamically linking it.
To resolve this, a new `no-webrtc` feature has been added to the
`live_kit_client` client crate and threaded through all of the crates
between it and the `extension_cli`.
Enabling the `no-webrtc` feature will prevent linking to the LiveKit
Swift SDK as well as linking the WebRTC framework.
Release Notes:
- N/A
I add /usr/lib/swift as an rpath, which seems to fix the issue even though
there doesn't seem to be a relevant library at that location on my machine.
Based on my research, wondering if `-Wl,-weak-lswiftCompatibilityConcurrency`
is also required for this to work on older OSes, but holding back for now.
