Use unique temp file prefix to avoid permission conflicts

- Change mktemp to use /tmp/pulse-config.XXXXXXXXXX template
- Prevents conflicts with stale temp files from previous runs
- Fixes 'Permission denied' errors when script re-runs

scripts/install-sensor-proxy.sh

@@ -68,9 +68,9 @@ update_allowed_nodes() {
     shift
     local nodes=("$@")
 
-    # Create temp file
+    # Create temp file with unique prefix to avoid conflicts
     local tmp_config
-    tmp_config=$(mktemp)
+    tmp_config=$(mktemp /tmp/pulse-config.XXXXXXXXXX)
 
     # Ensure temp file is cleaned up on exit (success or failure)
     trap "rm -f '$tmp_config'" RETURN