Add hs_* temp cleanup at START of sync (before Step 0)

sync.sh

@@ -1,4 +1,17 @@
 #!/bin/bash
+
+# ── Step 0.5: Clean stale temp directories from previous runs ────────────
+python3 << 'CLEANUP'
+import shutil, glob, os
+for prefix in ['hs_merge_', 'hs_exp_', 'hs_rest_']:
+    for d in glob.glob(os.path.join('/tmp', prefix + '*')):
+        try:
+            shutil.rmtree(d)
+            print(f'Cleaned: {d}')
+        except Exception as e:
+            print(f'Failed to clean {d}: {e}')
+CLEANUP
+
 set -e
 
 SYNC_DIR="${SYNC_DIR:-$HOME/.hermes-sync}"