Co-authored-by: Antonio Scandurra <me@as-cii.com>

Introduce support for C++

Co-authored-by: Antonio Scandurra <me@as-cii.com>

Co-Authored-By: Max Brunsfeld <max@zed.dev>

This makes it more evident that both languages share the same language
server.

Co-Authored-By: Max Brunsfeld <max@zed.dev>

Until the host has sent an UpdateProject message to populate the project's
metadata, there is no reason to update contacts.

* env_logger
* prost-build
* bindgen

* Make `UnregisterProject` a request. This way the client-side project can wait
  to clear out its remote id until the request has completed, so that the
  contacts panel can avoid showing duplicate private/public projects in the
  brief time after unregistering a project, before the next UpdateCollaborators
  message is received.
* Remove the `RegisterWorktree` and `UnregisterWorktree` methods and replace
  them with a single `UpdateProject` method that idempotently updates the
  Project's list of worktrees.

This prevents memory leak errors in tests, due to parked tasks waiting
for RPC responses.

Introduce a ProjectStore that lets you iterate through all open projects.
Allow projects to be made public by clicking the lock.

Report the correct app version when sending panics to server

Previously, we were just relying on the `ZED_APP_VERSION` environment
variable without consulting `Platform::app_version`. That would always
report "dev" as the app version because `ZED_APP_VERSION` is only used
for testing.

Don't reuse the same diagnostic group id across buffers

This lets us use the group id as the key for an `ElementState`, which
fixes a panic that would occur in project diagnostics when opening it
while there were multiple diagnostic groups with the same id.

Context menu polish

Jump to diagnostic

Now you simply specify a text, an action and a style and GPUI will
take of rendering it properly. This is simpler compared to always
providing a custom element and should make tooltip more consistent
across the UI.

This wraps and derefs to `RenderContext<Editor>`, so that we can
easily use `MouseEventHandler`s in blocks.

Improve server memory usage

We temporarily let it grow when the message size exceed the limit,
but restore the buffer's capacity shortly after. This ensures that,
for each connection in its entire lifetime, we only ever use 1MB.

Introduce context menu to project panel