refactor(build): reformat code and add tonic health dependency

- Reformatted build script with proper indentation and line breaks
- Added tonic-health dependency to Cargo.toml and updated lock file
- Improved error handling in disk cache with concurrent deletion checks
- Refactored conditional chains using && and let expressions
- Reformatted struct initialization and function parameter lists
- Added proper spacing and alignment in language stats processing
- Improved assertion formatting in test cases
- Reorganized import statements and code layout in multiple files
- Updated metrics functions with better parameter handling and formatting

server/pack.rs

@@ -1,9 +1,9 @@
 use tokio_stream::StreamExt;
 use tokio_stream::wrappers::ReceiverStream;
 
+use crate::pack::CancellableReceiverStream;
 use crate::pb::pack_service_client::PackServiceClient;
 use crate::pb::*;
-use crate::pack::CancellableReceiverStream;
 
 use super::{GitksService, into_status};