Added foundational modules for core functionalities:

- Introduced `walk.rs` as a parallel directory walker for search operations.
- Implemented basic index handling in `commands/index.rs`.
- Created `utils/config.rs` for configuration management with placeholders for future enhancements.

src/main.rs

@@ -0,0 +1,59 @@
+mod cli;
+mod commands;
+mod utils;
+
+use crate::utils::Config;
+use cli::Cli;
+use clap::Parser;
+use directories::ProjectDirs;
+use std::fs;
+
+use tracing_subscriber::{fmt, EnvFilter, Registry};
+use tracing_subscriber::prelude::*;
+use tracing_subscriber::fmt::time;
+
+// use tracing_appender::rolling::{RollingFileAppender, Rotation};
+// use tracing_appender::non_blocking;
+
+fn init_tracing() {
+    // let file_appender = RollingFileAppender::new(Rotation::HOURLY, "logs", "nano-scanner.log");
+    // let (file_writer, guard) = non_blocking(file_appender);
+    
+    let fmt_layer = fmt::layer()
+        .pretty()                           
+        .with_thread_ids(true)     
+        .with_timer(time::UtcTime::rfc_3339());
+    
+    // let file_layer = fmt::layer()
+    //     .with_writer(file_writer)          
+    //     .without_time()                     
+    //     .json();
+
+    Registry::default()
+        .with(EnvFilter::from_default_env()) // obey RUST_LOG
+        .with(fmt_layer)         
+        .init();                             // install as the global subscriber
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    init_tracing();
+
+    tracing::debug!("CLI starting up");
+    let cli = Cli::parse();
+
+    let proj_dirs = ProjectDirs::from("dev", "ecpeter23", "nano")
+        .ok_or("Unable to determine project directories")?;
+
+    let config_dir = proj_dirs.config_dir();
+    fs::create_dir_all(config_dir)?;
+
+    let database_dir = proj_dirs.data_local_dir();
+    fs::create_dir_all(database_dir)?;
+
+    let config = Config::load(config_dir)?;
+
+    commands::handle_command(cli.command, database_dir, &config)?;
+
+    Ok(())
+}
+