test(backend): add RPT log output to server stub

- Stub now parses -profiles= arg and writes RPT entries to
  profilesDir/arma3server_x64_<timestamp>.rpt
- RPT includes header (exe timestamp, computer name, OS) and periodic
  entries (MissionEditor, World, Server: Player) on each heartbeat cycle
- New test TestStart_StubWritesRPTLog verifies RPT file creation and
  content via the profiles directory

backend/internal/services/server_process_test.go

@@ -773,3 +773,77 @@ func TestStart_StubAutoExit(t *testing.T) {
 		t.Error("IsRunning() should be false after stub auto-exited (timeout 2s)")
 	}
 }
+
+func TestStart_StubWritesRPTLog(t *testing.T) {
+	dir := t.TempDir()
+	serverfileDir := filepath.Join(dir, "server")
+	profilesDir := filepath.Join(dir, "profiles")
+	modsDir := filepath.Join(dir, "mods")
+	cfgDir := filepath.Join(dir, "cfg")
+	os.MkdirAll(serverfileDir, 0755)
+
+	stubSrc, _ := os.ReadFile("testdata/arma3server_x64")
+	os.WriteFile(filepath.Join(serverfileDir, "arma3server_x64"), stubSrc, 0755)
+
+	sm := NewSettingsManager(dir)
+	mm := NewModlistManager(filepath.Join(dir, "modlists"))
+	cm := NewConfigManager(cfgDir)
+	streamer := NewLogStreamer()
+
+	pm := NewProcessManager(serverfileDir, modsDir, cfgDir, profilesDir, sm, mm, cm, streamer)
+
+	s, _ := sm.Load()
+	s.ServerParameters = "-t 7"
+	sm.Save(s)
+
+	if err := pm.Start(); err != nil {
+		t.Fatalf("Start() error = %v", err)
+	}
+
+	// Wait for the stub to write RPT entries (heartbeat at ~5s)
+	deadline := time.Now().Add(8 * time.Second)
+	var rptPath string
+	for time.Now().Before(deadline) {
+		matches, _ := filepath.Glob(filepath.Join(profilesDir, "arma3server_x64_*.rpt"))
+		if len(matches) > 0 {
+			rptPath = matches[0]
+			break
+		}
+		time.Sleep(200 * time.Millisecond)
+	}
+
+	if rptPath == "" {
+		pm.Stop()
+		t.Fatal("RPT file not found in profiles dir")
+	}
+
+	// Wait for heartbeat entries to be written (heartbeat at ~5s)
+	deadline2 := time.Now().Add(6 * time.Second)
+	for time.Now().Before(deadline2) {
+		data, _ := os.ReadFile(rptPath)
+		if strings.Contains(string(data), "MissionEditor") {
+			break
+		}
+		time.Sleep(500 * time.Millisecond)
+	}
+
+	data, err := os.ReadFile(rptPath)
+	if err != nil {
+		pm.Stop()
+		t.Fatalf("ReadFile(%s) error = %v", rptPath, err)
+	}
+
+	content := string(data)
+	if !strings.Contains(content, "RPT log started") {
+		t.Errorf("RPT missing header, got:\n%s", content)
+	}
+	if !strings.Contains(content, "MissionEditor") {
+		t.Errorf("RPT missing MissionEditor entry, got:\n%s", content)
+	}
+	if !strings.Contains(content, "Server: Player") {
+		t.Errorf("RPT missing Server: Player entry, got:\n%s", content)
+	}
+
+	pm.Stop()
+	time.Sleep(100 * time.Millisecond)
+}

backend/internal/services/testdata/arma3server_x64

@@ -1,17 +1,39 @@
 #!/bin/sh
 # Stub arma3server binary for testing.
 # Logs binary path and all arguments, prints heartbeat every 5s.
+# Writes RPT log entries to the profiles directory (like the real server).
 # Use -t N to exit after N seconds (for auto-exit tests).
+
 echo "[STUB] binary=$0 args=$*"
 
 DURATION=0
+PROFILES_DIR=""
 while [ $# -gt 0 ]; do
   case "$1" in
     -t) DURATION="$2"; shift 2 ;;
+    -profiles=*) PROFILES_DIR="${1#-profiles=}"; shift ;;
     *)  shift ;;
   esac
 done
 
+# Create RPT file in profiles dir if provided
+RPT_FILE=""
+if [ -n "$PROFILES_DIR" ]; then
+  mkdir -p "$PROFILES_DIR"
+  RPT_FILE="$PROFILES_DIR/arma3server_x64_$(date +%Y%m%d_%H%M%S).rpt"
+  echo "--- RPT log started ---" > "$RPT_FILE"
+  echo "Exe timestamp: 2024/01/15 12:00:00" >> "$RPT_FILE"
+  echo "Computer name: STUB-TEST" >> "$RPT_FILE"
+  echo "Operating system: Linux" >> "$RPT_FILE"
+fi
+
+write_rpt() {
+  if [ -n "$RPT_FILE" ]; then
+    echo "$1" >> "$RPT_FILE"
+  fi
+}
+
+TICK=0
 if [ "$DURATION" -gt 0 ] 2>/dev/null; then
   ELAPSED=0
   while [ "$ELAPSED" -lt "$DURATION" ]; do
@@ -20,12 +42,21 @@ if [ "$DURATION" -gt 0 ] 2>/dev/null; then
     if [ "$REMAINING" -lt 5 ]; then WAIT=$REMAINING; fi
     sleep "$WAIT"
     ELAPSED=$((ELAPSED + WAIT))
+    TICK=$((TICK + 1))
     echo "[STUB] heartbeat elapsed=${ELAPSED}s remaining=$((REMAINING - WAIT))s"
+    write_rpt "$(date +%H:%M:%S) MissionEditor: Mission file selected: test_mission.Tanoa"
+    write_rpt "$(date +%H:%M:%S) World: Avoid neighbor island: 0.00 ms (1.00 ms)"
+    write_rpt "$(date +%H:%M:%S) Server: Player #1 connected (id=12345)"
   done
+  write_rpt "$(date +%H:%M:%S) Server: Shutdown completed"
   echo "[STUB] server exiting after ${DURATION}s"
 else
   while true; do
     sleep 5
+    TICK=$((TICK + 1))
     echo "[STUB] heartbeat running..."
+    write_rpt "$(date +%H:%M:%S) MissionEditor: Mission file selected: test_mission.Tanoa"
+    write_rpt "$(date +%H:%M:%S) World: Avoid neighbor island: 0.00 ms (1.00 ms)"
+    write_rpt "$(date +%H:%M:%S) Server: Player #1 connected (id=12345)"
   done
 fi