feat: auto-install libusb on Windows from bundled DLL

- installLibusb now extracts libusb-1.0.dll from payload to install dir
- Falls back to winget, then shows Zadig download link
- checkLibusbInstalled also checks install directory
- CI workflow copies libusb-1.0.dll into payload during staging

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitea/workflows/build-installer.yaml

@@ -114,6 +114,7 @@ jobs:
           Copy-Item "$base\scripts\kneron_detect.py" "$base\installer\payload\scripts\"
           Copy-Item "$base\server\scripts\firmware\KL520\*.bin" "$base\installer\payload\scripts\firmware\KL520\"
           Copy-Item "$base\server\scripts\firmware\KL720\*.bin" "$base\installer\payload\scripts\firmware\KL720\"
+          Copy-Item "local_service_win\third_party\Kneron_DFUT\bin\libusb-1.0.dll" "$base\installer\payload\scripts\"
 
       - name: Build Windows installer
         run: |

.github/workflows/build-installer.yaml

@@ -114,6 +114,7 @@ jobs:
           Copy-Item "$base\scripts\kneron_detect.py" "$base\installer\payload\scripts\"
           Copy-Item "$base\server\scripts\firmware\KL520\*.bin" "$base\installer\payload\scripts\firmware\KL520\"
           Copy-Item "$base\server\scripts\firmware\KL720\*.bin" "$base\installer\payload\scripts\firmware\KL720\"
+          Copy-Item "local_service_win\third_party\Kneron_DFUT\bin\libusb-1.0.dll" "$base\installer\payload\scripts\"
 
       - name: Build Windows installer
         run: |

edge-ai-platform/installer/platform_windows.go

@@ -71,24 +71,50 @@ func removeSystemLink() {
 }
 
 func installLibusb(installDir string) error {
-	// Check known system DLL locations
-	dllPaths := []string{
+	// Check if already present in system or install directory
+	checkPaths := []string{
 		filepath.Join(os.Getenv("SystemRoot"), "System32", "libusb-1.0.dll"),
 		filepath.Join(os.Getenv("SystemRoot"), "SysWOW64", "libusb-1.0.dll"),
+		filepath.Join(installDir, "libusb-1.0.dll"),
 	}
-	for _, p := range dllPaths {
+	for _, p := range checkPaths {
 		if _, err := os.Stat(p); err == nil {
 			return nil // already installed
 		}
 	}
 
-	return fmt.Errorf("libusb not found. Please install the WinUSB driver via Zadig: https://zadig.akeo.ie")
+	// Try to extract libusb-1.0.dll from payload to install directory
+	// The DLL is bundled at payload/scripts/libusb-1.0.dll
+	dllDest := filepath.Join(installDir, "libusb-1.0.dll")
+	data, err := payloadFS.ReadFile("payload/scripts/libusb-1.0.dll")
+	if err == nil {
+		if writeErr := os.WriteFile(dllDest, data, 0644); writeErr == nil {
+			return nil // successfully extracted
+		}
+	}
+
+	// Fallback: try winget
+	if wingetPath, err := exec.LookPath("winget"); err == nil {
+		cmd := exec.Command(wingetPath, "install", "libusb",
+			"--accept-source-agreements", "--accept-package-agreements", "--silent")
+		cmd.Run() // best effort
+
+		// Re-check
+		for _, p := range checkPaths {
+			if _, err := os.Stat(p); err == nil {
+				return nil
+			}
+		}
+	}
+
+	return fmt.Errorf("libusb not found. For Kneron USB device support, install the WinUSB driver via Zadig: https://zadig.akeo.ie")
 }
 
 func checkLibusbInstalled() bool {
 	dllPaths := []string{
 		filepath.Join(os.Getenv("SystemRoot"), "System32", "libusb-1.0.dll"),
 		filepath.Join(os.Getenv("SystemRoot"), "SysWOW64", "libusb-1.0.dll"),
+		filepath.Join(platformDefaultDir(), "libusb-1.0.dll"),
 	}
 	for _, p := range dllPaths {
 		if _, err := os.Stat(p); err == nil {