This PR introduces a new `command_palette_hooks` crate that contains the
types used to hook into the behavior of the command palette.
The `CommandPaletteFilter` was previously extracted to the `copilot`
crate in #7095, solely because that was the earliest ancestor of the
crates that depended on it.
The `CommandPaletteInterceptor` was still defined in `command_palette`
itself.
Both of these types were consumed by other crates wanting to influence
the behavior of the command palette, but required taking a dependency on
the entire `command_palette` crate in order to gain access to these
hooks.
By moving them out into their own crate, we can improve the compile
order and make crates like `vim` able to begin building sooner without
having to wait for `command_palette` to finish compiling.
Here's a comparison of the compilation graph before and after (ignore
the timings):
#### Before
<img width="332" alt="Screenshot 2024-02-25 at 12 42 29 PM"
src="https://github.com/zed-industries/zed/assets/1486634/a57c662e-fbc2-41ab-9e30-cca17afa6c73">
#### After
<img width="362" alt="Screenshot 2024-02-25 at 12 51 15 PM"
src="https://github.com/zed-industries/zed/assets/1486634/c1a6d29c-b607-4604-8f1b-e5d318bf8849">
Release Notes:
- N/A
