Include the desired version in a SaveBuffer RPC request

When handling this messages on the host, wait until the desired
version has been observed before performing the save.

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

crates/project/src/worktree.rs

@@ -1404,6 +1404,7 @@ impl language::File for File {
                         .request(proto::SaveBuffer {
                             project_id,
                             buffer_id,
+                            version: (&version).into(),
                         })
                         .await?;
                     let version = response.version.try_into()?;