fix: update remaining go-onvif references to onvif-go for complete branding consistency

- server/types.go: Manufacturer identifier 'go-onvif' → 'onvif-go'
- cmd/onvif-server/main.go: Manufacturer flag default 'go-onvif' → 'onvif-go'
- server/README.md: Documentation updated
- examples/manual-soap-test/main.go: Code comments updated (2 instances)
- examples/complete-demo/main.go: Code comment updated

Now using 'onvif-go' consistently across all project files, including
device identifiers, code comments, and documentation.

server/README.md

@@ -95,7 +95,7 @@ The server will start on `http://0.0.0.0:8080` with:
   -password string
         Authentication password (default "admin")
   -manufacturer string
-        Device manufacturer (default "go-onvif")
+        Device manufacturer (default "onvif-go")
   -model string
         Device model (default "Virtual Multi-Lens Camera")
   -firmware string

server/types.go

@@ -235,7 +235,7 @@ func DefaultConfig() *Config {
 		BasePath: "/onvif",
 		Timeout:  30 * time.Second,
 		DeviceInfo: DeviceInfo{
-			Manufacturer:    "go-onvif",
+			Manufacturer:    "onvif-go",
 			Model:           "Virtual Multi-Lens Camera",
 			FirmwareVersion: "1.0.0",
 			SerialNumber:    "SN-12345678",