Introducing the Active File Context portion of #9705. When someone is in
the assistant panel it now includes the active file as a system message
on send while showing them a nice little display in the lower right:
For this iteration, I'd love to see the following before we land this:
* [x] Toggle-able context - user should be able to disable sending this
context
* [x] Show nothing if there is no context coming in
* [x] Update token count as we change items
* [x] Listen for a more finely scoped event for when the active item
changes
* [x] Create a global for pulling a file icon based on a path. Zed's
main way to do this is nested within project panel's `FileAssociation`s.
* [x] Get the code fence name for a Language for the system prompt
* [x] Update the token count when the buffer content changes
I'm seeing this PR as the foundation for providing other kinds of
context -- diagnostic summaries, failing tests, additional files, etc.
Release Notes:
- Added file context to assistant chat panel
([#9705](https://github.com/zed-industries/zed/issues/9705)).
<img width="1558" alt="image"
src="https://github.com/zed-industries/zed/assets/836375/86eb7e50-3e28-4754-9c3f-895be588616d">
---------
Co-authored-by: Conrad Irwin <conrad@zed.dev>
Co-authored-by: Nathan <nathan@zed.dev>
Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Mikayla Maki <mikayla@zed.dev>
This PR extracts C# support into an extension and removes the built-in
C# support from Zed.
Tested using a Nix shell:
```
nix-shell -p dotnet-sdk omnisharp-roslyn
```
Release Notes:
- Removed built-in support for C#, in favor of making it available as an
extension. The C# extension will be suggested for download when you open
a `.cs` file.
