Add the ability to edit remote directories over SSH (#14530)

This is a first step towards allowing you to edit remote projects
directly over SSH. We'll start with a pretty bare-bones feature set, and
incrementally add further features.

### Todo

Distribution
* [x] Build nightly releases of `zed-remote-server` binaries
    * [x] linux (arm + x86)
    * [x] mac (arm + x86)
* [x] Build stable + preview releases of `zed-remote-server`
* [x] download and cache remote server binaries as needed when opening
ssh project
* [x] ensure server has the latest version of the binary


Auth
* [x] allow specifying password at the command line
* [x] auth via ssh keys
* [x] UI password prompt

Features
* [x] upload remote server binary to server automatically
* [x] opening directories
* [x] tracking file system updates
* [x] opening, editing, saving buffers
* [ ] file operations (rename, delete, create)
* [ ] git diffs
* [ ] project search

Release Notes:

- N/A

---------

Co-authored-by: Piotr Osiewicz <24362066+osiewicz@users.noreply.github.com>

crates/collab/src/tests/test_server.rs

@@ -25,6 +25,7 @@ use node_runtime::FakeNodeRuntime;
 use notifications::NotificationStore;
 use parking_lot::Mutex;
 use project::{Project, WorktreeId};
+use remote::SshSession;
 use rpc::{
     proto::{self, ChannelRole},
     RECEIVE_TIMEOUT,
@@ -814,6 +815,30 @@ impl TestClient {
         (project, worktree.read_with(cx, |tree, _| tree.id()))
     }
 
+    pub async fn build_ssh_project(
+        &self,
+        root_path: impl AsRef<Path>,
+        ssh: Arc<SshSession>,
+        cx: &mut TestAppContext,
+    ) -> (Model<Project>, WorktreeId) {
+        let project = cx.update(|cx| {
+            Project::ssh(
+                ssh,
+                self.client().clone(),
+                self.app_state.node_runtime.clone(),
+                self.app_state.user_store.clone(),
+                self.app_state.languages.clone(),
+                self.app_state.fs.clone(),
+                cx,
+            )
+        });
+        let (worktree, _) = project
+            .update(cx, |p, cx| p.find_or_create_worktree(root_path, true, cx))
+            .await
+            .unwrap();
+        (project, worktree.read_with(cx, |tree, _| tree.id()))
+    }
+
     pub async fn build_test_project(&self, cx: &mut TestAppContext) -> Model<Project> {
         self.fs()
             .insert_tree(