fix(job): clean up stale handles before copy check, add -i flag

Stale finished handles in try_copy caused running_count() > 0,
permanently blocking build-to-run copies after git pull updates.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: aster-void

src/actor/job/mod.rs

@@ -62,6 +62,7 @@ impl JobActor {
     }
 
     fn try_copy(&mut self) -> anyhow::Result<bool> {
+        self.cleanup_finished_handles();
         if self.pending_copy && self.running_count() == 0 {
             info!(target: "rollcron::job", job_id = %self.job.id, "Copying build to run directory");
             let build_dir = git::get_build_dir(&self.sot_path, &self.job.id);

src/main.rs

@@ -22,7 +22,7 @@ struct Args {
     repo: String,
 
     /// Pull interval in seconds
-    #[arg(long, default_value = "3600")]
+    #[arg(short = 'i', long, default_value = "3600")]
     pull_interval: u64,
 }