fix(ci): Add -s flag to rnsd to enable log file creation

The validation script checks ~/.reticulum/logfile for BLE interface
status, but this file is only created when rnsd is started with the
-s (service/syslog) flag.

Without -s flag:
- rnsd runs but doesn't write to ~/.reticulum/logfile
- Validation script fails: "Log file not found"
- Deployment appears successful but validation always fails

With -s flag:
- rnsd writes logs to ~/.reticulum/logfile
- Validation can check for "interface online" message
- Full deployment + validation cycle works

Note: Only affects manual rnsd startup (non-systemd path). Systemd
installations should have -s configured in the service file.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

.github/workflows/deploy.yml

@@ -147,7 +147,7 @@ jobs:
           else
             pkill -9 rnsd 2>/dev/null || true
             sleep 1
-            nohup \"\$RNSD_BIN\" > /dev/null 2>&1 &
+            nohup \"\$RNSD_BIN\" -s > /dev/null 2>&1 &
             sleep 2
             if pgrep -x rnsd > /dev/null; then
               echo '  ✓ rnsd started successfully'