fix(v3/webview2): use log instead of fmt for error and stack trace output (#5453)

On Windows, especially in production applications started outside of a
terminal, fmt.Println / fmt.Printf output is often not visible because
there is no attached console, so error messages and stack traces from
the WebView2 global error handler are lost. Routing them through the
log package ensures they reach the standard logger destination.

Ports wailsapp/go-webview2#35 to the vendored webview2 package.

Co-authored-by: Andrey Pshenkin <andrey.pshenkin@gmail.com>

Author: leaanthony

v3/UNRELEASED_CHANGELOG.md

@@ -25,6 +25,7 @@ After processing, the content will be moved to the main changelog and this file
 ## Fixed
 <!-- Bug fixes -->
 - Fix `concurrent map read and map write` runtime fatal in `linuxSystemTray` when the tray menu is updated while the panel reads it.
+- Use `log` instead of `fmt` for WebView2 error and stack trace output so messages aren't lost when the app runs without an attached console on Windows.
 
 ## Deprecated
 <!-- Soon-to-be removed features -->

webview2/pkg/edge/chromium.go

@@ -28,13 +28,13 @@ func globalErrorHandler(err error) {
 		return
 	}
 
-	fmt.Printf("[WebView2 Error] %v\n", err)
+	log.Printf("[WebView2 Error] %v\n", err)
 
 	stackBuf := make([]uintptr, 64)
 	stackSize := runtime.Callers(2, stackBuf)
 	frames := runtime.CallersFrames(stackBuf[:stackSize])
 
-	fmt.Println("\nStack trace:")
+	log.Printf("\nStack trace:")
 	stackIndex := 1
 	for {
 		frame, more := frames.Next()