- Rename index.rs to database.rs for clarity in purpose

- Update references in `scan.rs` to the renamed module
- Add `cargo clippy` step to CI for linting

src/main.rs

@@ -2,7 +2,7 @@ mod cli;
 mod commands;
 mod utils;
 mod walk;
-mod index;
+mod database;
 
 use crate::utils::Config;
 use cli::Cli;