feat: add cleanup option for auto-installed dependencies in build command

- Introduced a new `cleanup_deps` flag in the build command to remove dependencies that were automatically installed during the build process.
- Implemented an `InterruptWatcher` to handle Ctrl-C interruptions gracefully during the build process.
- Enhanced the `AutoInstalledDependencyTracker` to track and manage auto-installed dependencies, allowing for cleanup after the build.
- Updated the CLI to parse the new `cleanup_deps` flag and integrated it into the build workflow.
- Added tests to ensure the correct parsing of the `cleanup_deps` flag and the functionality of the dependency tracking and cleanup process.
- Improved logging for package removal operations to include a verbose mode controlled by the `DEPOT_VERBOSE_REMOVE` environment variable.

src/cli.rs

@@ -97,6 +97,10 @@ pub enum Commands {
         /// Automatically install missing dependencies before building
         #[arg(long)]
         install_deps: bool,
+
+        /// Remove dependencies auto-installed for this build after the command finishes
+        #[arg(long)]
+        cleanup_deps: bool,
     },
     /// Update installed packages from configured repositories
     Update {
@@ -360,4 +364,13 @@ mod tests {
             _ => panic!("expected build command"),
         }
     }
+
+    #[test]
+    fn build_cleanup_deps_flag_is_parsed() {
+        let cli = Cli::try_parse_from(["depot", "build", "--cleanup-deps", "pkg.toml"]).unwrap();
+        match cli.command {
+            Commands::Build { cleanup_deps, .. } => assert!(cleanup_deps),
+            _ => panic!("expected build command"),
+        }
+    }
 }