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/internal/builder/handler_helpers_test.go

@@ -167,3 +167,30 @@ func TestShouldSignBuildNoRequestFlag(t *testing.T) {
 		t.Fatal("SignBuild flag required")
 	}
 }
+
+func TestBuildExtraFilesFromArtifacts(t *testing.T) {
+	if got := buildExtraFilesFromArtifacts(nil); got != nil {
+		t.Fatalf("nil input should return nil, got %+v", got)
+	}
+	if got := buildExtraFilesFromArtifacts([]BuildArtifactFile{}); got != nil {
+		t.Fatalf("empty slice should return nil, got %+v", got)
+	}
+	arts := []BuildArtifactFile{
+		{FileName: "readme.txt", FilePath: "/tmp/readme.txt"},
+		{FileName: "runner.exe", FilePath: "/tmp/runner.exe"},
+	}
+	got := buildExtraFilesFromArtifacts(arts)
+	if len(got) != 2 {
+		t.Fatalf("expected 2 extras, got %d", len(got))
+	}
+	if got[0].FileName != "readme.txt" || got[0].FilePath != "/tmp/readme.txt" {
+		t.Fatalf("first artifact: %+v", got[0])
+	}
+}
+
+func TestFusionUniversalStartShBareExtension(t *testing.T) {
+	sh := fusionUniversalStartSh(".pdf")
+	if !strings.Contains(sh, "-runner") {
+		t.Fatalf("expected runner suffix in script: %q", sh)
+	}
+}