Differentiate between follow state on a per-project basis

crates/collab/src/db.rs

@@ -1996,6 +1996,7 @@ impl Database {
             followers.push(proto::Follower {
                 leader_id: Some(db_follower.leader_connection().into()),
                 follower_id: Some(db_follower.follower_connection().into()),
+                project_id: db_follower.project_id.to_proto(),
             });
         }
 

crates/collab/src/tests/integration_tests.rs

@@ -5934,7 +5934,7 @@ async fn test_following(
         active_call.read_with(*cx, |call, cx| {
             let room = call.room().unwrap().read(cx);
             assert_eq!(
-                room.followers_for(peer_id_a),
+                room.followers_for(peer_id_a, project_id),
                 &[peer_id_b, peer_id_c],
                 "checking followers for A as {name}"
             );
@@ -5956,7 +5956,7 @@ async fn test_following(
         active_call.read_with(*cx, |call, cx| {
             let room = call.room().unwrap().read(cx);
             assert_eq!(
-                room.followers_for(peer_id_a),
+                room.followers_for(peer_id_a, project_id),
                 &[peer_id_b],
                 "checking followers for A as {name}"
             );