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/models/agent_test.go

@@ -153,6 +153,7 @@ func TestBuildRecordJSONRoundTrip(t *testing.T) {
 		Threads: 4, FileSize: 1024, BundleSize: 2048,
 		FilePath: "/data/build.exe", FileName: "build.exe",
 		DownloadURL: "/api/v1/builds/build-1/download", Platform: "windows",
+		ExtraFiles: []BuildExtraFile{{FileName: "README.txt"}},
 		CreatedAt: time.Now().UTC(), Pinned: true,
 		PoolHost: "pool.example.com", PoolPort: 3333, PoolTLS: true, PoolPass: "x",
 	})