Fix update output index hang

[Oscar-Pepper]

• moves targetted rescan to its own function with tokio tasks and joins handle with other sync tasks
• uses the full tx fetcher sender instead of fetch full tx sender as fetch full tx can only scan transactions in the current batch or will hang
• adds a targetted rescan test where the output index is missing and is recovered
• unifies timestamps in sync functions to u32 which is the original data type from the compact block itself