Add thiserror and improve console output formatting

- Added `thiserror` dependency in `Cargo.toml` and `Cargo.lock` for enhanced error handling.
- Improved execution time tracking and output formatting in `main.rs`.
- Refactored console output in `scan.rs` for better readability with grouped warnings.
- Simplified error handling in `scan_filesystem`.

Cargo.lock

@@ -514,6 +514,7 @@ dependencies = [
  "rayon",
  "rusqlite",
  "serde",
+ "thiserror",
  "toml",
  "tracing",
  "tracing-subscriber",