Separate repository state synchronization from worktree synchronization (#27140)

This PR updates our DB schemas and wire protocol to separate the
synchronization of git statuses and other repository state from the
synchronization of worktrees. This paves the way for moving the code
that executes git status updates out of the `worktree` crate and onto
the new `GitStore`. That end goal is motivated by two (related) points:

- Disentangling git status updates from the worktree's
`BackgroundScanner` will allow us to implement a simpler concurrency
story for those updates, hopefully fixing some known but elusive bugs
(upstream state not updating after push; statuses getting out of sync in
remote projects).
- By moving git repository state to the project-scoped `GitStore`, we
can get rid of the duplication that currently happens when two worktrees
are associated with the same git repository.

Co-authored-by: Max <max@zed.dev>

Release Notes:

- N/A

---------

Co-authored-by: Max <max@zed.dev>
Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>

crates/collab/src/rpc.rs

@@ -37,6 +37,7 @@ use core::fmt::{self, Debug, Formatter};
 use http_client::HttpClient;
 use open_ai::{OpenAiEmbeddingModel, OPEN_AI_API_URL};
 use reqwest_client::ReqwestClient;
+use rpc::proto::split_repository_update;
 use sha2::Digest;
 use supermaven_api::{CreateExternalUserRequest, SupermavenAdminApi};
 
@@ -291,6 +292,8 @@ impl Server {
             .add_message_handler(leave_project)
             .add_request_handler(update_project)
             .add_request_handler(update_worktree)
+            .add_request_handler(update_repository)
+            .add_request_handler(remove_repository)
             .add_message_handler(start_language_server)
             .add_message_handler(update_language_server)
             .add_message_handler(update_diagnostic_summary)
@@ -1464,7 +1467,7 @@ fn notify_rejoined_projects(
                 removed_repositories: worktree.removed_repositories,
             };
             for update in proto::split_worktree_update(message) {
-                session.peer.send(session.connection_id, update.clone())?;
+                session.peer.send(session.connection_id, update)?;
             }
 
             // Stream this worktree's diagnostics.
@@ -1493,21 +1496,23 @@ fn notify_rejoined_projects(
             }
         }
 
-        for language_server in &project.language_servers {
+        for repository in mem::take(&mut project.updated_repositories) {
+            for update in split_repository_update(repository) {
+                session.peer.send(session.connection_id, update)?;
+            }
+        }
+
+        for id in mem::take(&mut project.removed_repositories) {
             session.peer.send(
                 session.connection_id,
-                proto::UpdateLanguageServer {
+                proto::RemoveRepository {
                     project_id: project.id.to_proto(),
-                    language_server_id: language_server.id,
-                    variant: Some(
-                        proto::update_language_server::Variant::DiskBasedDiagnosticsUpdated(
-                            proto::LspDiskBasedDiagnosticsUpdated {},
-                        ),
-                    ),
+                    id,
                 },
             )?;
         }
     }
+
     Ok(())
 }
 
@@ -1893,7 +1898,7 @@ fn join_project_internal(
             removed_entries: Default::default(),
             scan_id: worktree.scan_id,
             is_last_update: worktree.scan_id == worktree.completed_scan_id,
-            updated_repositories: worktree.repository_entries.into_values().collect(),
+            updated_repositories: worktree.legacy_repository_entries.into_values().collect(),
             removed_repositories: Default::default(),
         };
         for update in proto::split_worktree_update(message) {
@@ -1926,6 +1931,12 @@ fn join_project_internal(
         }
     }
 
+    for repository in mem::take(&mut project.repositories) {
+        for update in split_repository_update(repository) {
+            session.peer.send(session.connection_id, update)?;
+        }
+    }
+
     for language_server in &project.language_servers {
         session.peer.send(
             session.connection_id,
@@ -2018,6 +2029,54 @@ async fn update_worktree(
     Ok(())
 }
 
+async fn update_repository(
+    request: proto::UpdateRepository,
+    response: Response<proto::UpdateRepository>,
+    session: Session,
+) -> Result<()> {
+    let guest_connection_ids = session
+        .db()
+        .await
+        .update_repository(&request, session.connection_id)
+        .await?;
+
+    broadcast(
+        Some(session.connection_id),
+        guest_connection_ids.iter().copied(),
+        |connection_id| {
+            session
+                .peer
+                .forward_send(session.connection_id, connection_id, request.clone())
+        },
+    );
+    response.send(proto::Ack {})?;
+    Ok(())
+}
+
+async fn remove_repository(
+    request: proto::RemoveRepository,
+    response: Response<proto::RemoveRepository>,
+    session: Session,
+) -> Result<()> {
+    let guest_connection_ids = session
+        .db()
+        .await
+        .remove_repository(&request, session.connection_id)
+        .await?;
+
+    broadcast(
+        Some(session.connection_id),
+        guest_connection_ids.iter().copied(),
+        |connection_id| {
+            session
+                .peer
+                .forward_send(session.connection_id, connection_id, request.clone())
+        },
+    );
+    response.send(proto::Ack {})?;
+    Ok(())
+}
+
 /// Updates other participants with changes to the diagnostics
 async fn update_diagnostic_summary(
     message: proto::UpdateDiagnosticSummary,