Improve portable launch, forge persistence, and operator auth UX.

Persist build extra_files for Build Manager history, print dashboard login on every start, add libp2p for Mesh P2P forge, defer WebSocket until login, and split devrun.bat from LAUNCH.bat with USB deck auto-detection.

server/main.go

@@ -94,6 +94,9 @@ func main() {
 		}
 	}
 
+	// Load dashboard auth early so credentials print before slow startup steps.
+	api.LoadUsers(cfg.DataDir)
+
 	// Initialize database
 	database, err := db.New(cfg.DataDir)
 	if err != nil {
@@ -182,6 +185,7 @@ func main() {
 	log.Println("Config handler initialized")
 
 	maintenance.StartRetentionJobs(database, cfg.DataDir, cfg.Server.StatsRetentionHours, cfg.Server.BuildRetentionDays)
+	defer maintenance.StopRetentionJobs()
 
 	// Pre-connect default upstream pool from server config (Forge defaults seed from here)
 	go func() {
@@ -422,13 +426,23 @@ func resolveDataDir(dataDir, projectRoot string) string {
 	return abs
 }
 
+func projectRootMarker(dir string) bool {
+	for _, name := range []string{"devrun.bat", "LAUNCH.bat", "run.bat"} {
+		if _, err := os.Stat(filepath.Join(dir, name)); err == nil {
+			return true
+		}
+	}
+	return false
+}
+
 func findProjectRoot() string {
 	if cwd, err := os.Getwd(); err == nil {
-		if _, err := os.Stat(filepath.Join(cwd, "run.bat")); err == nil {
+		if projectRootMarker(cwd) {
 			return cwd
 		}
-		if _, err := os.Stat(filepath.Join(filepath.Dir(cwd), "run.bat")); err == nil {
-			return filepath.Dir(cwd)
+		parent := filepath.Dir(cwd)
+		if projectRootMarker(parent) {
+			return parent
 		}
 	}
 	if exe, err := os.Executable(); err == nil {
@@ -439,7 +453,7 @@ func findProjectRoot() string {
 			filepath.Join(exeDir, "..", ".."),
 		}
 		for _, candidate := range candidates {
-			if _, err := os.Stat(filepath.Join(candidate, "run.bat")); err == nil {
+			if projectRootMarker(candidate) {
 				abs, _ := filepath.Abs(candidate)
 				return abs
 			}
@@ -454,7 +468,7 @@ func findProjectRoot() string {
 // findWebRoot locates the frontend build output directory
 func findWebRoot() string {
 	candidates := []string{
-		"webroot",  // Copied by run.bat
+		"webroot",  // Copied by devrun.bat
 		"web/dist", // Vite build output relative to server/
 		filepath.Join("..", "server", "web", "dist"), // Relative to project root
 		filepath.Join("server", "web", "dist"),       // From project root