[management,client] 0.75.0 release with new desktop UI (#6473)

- **Wails v3 application** (`client/ui`) with a React + TypeScript + Tailwind frontend replacing the Fyne UI: main connection view, exit-node switcher, networks/peers browser with detail panels, profile management, settings (general, network, SSH, security, troubleshooting, appearance), debug-bundle creation, and a first-run welcome flow.
- **Internationalization**: go-i18n bundle with 9 locales (en, de, es, fr, hu, it, pt, ru, zh-CN) shared between the tray and the frontend.
- **New system tray** implementation with per-platform theme-aware icons, including a native XEmbed host for Linux (`xembed_tray_linux.c`) and a Linux theme watcher.
- **Session handling**: auth session watcher (`client/internal/auth/sessionwatch`), pending login flow, session-expiration dialog and tray notifications, and `netbird login` improvements.
- **Daemon API extensions** (`daemon.proto`): status stream subscription, event stream, networks/exit-node selection endpoints, and richer full status — with probe throttling on the daemon side to protect against UI-driven request storms.
- **UI preferences store** persisted per profile, autostart management via the daemon (single source of truth in HKCU on Windows).
- **Build system**: Taskfile-based builds per platform (macOS, Linux, Windows), Docker cross-compilation images, MSIX/NSIS/nfpm/AppImage packaging, and a new `frontend-ui` CI workflow.

Co-authored-by: Zoltan Papp <zoltan.pmail@gmail.com>
Co-authored-by: Eduard Gert <kontakt@eduardgert.de>
Co-authored-by: braginini <bangvalo@gmail.com>
Co-authored-by: Pascal Fischer <32096965+pascal-fischer@users.noreply.github.com>
Co-authored-by: riccardom <riccardomanfrin@gmail.com>

client/ui/uilogpath.go

@@ -0,0 +1,37 @@
+//go:build !android && !ios && !freebsd && !js
+
+package main
+
+import (
+	"os"
+	"path/filepath"
+
+	log "github.com/sirupsen/logrus"
+
+	"github.com/netbirdio/netbird/client/ui/guilog"
+)
+
+// uiLogFileName must stay in sync with the daemon's "gui-client*.log.*" glob
+// for rotated siblings (addUILog in client/internal/debug).
+const uiLogFileName = "gui-client.log"
+
+// uiLogPath returns the GUI log path with native separators, since the daemon
+// opens it directly for debug-bundle collection.
+func uiLogPath() (string, error) {
+	dir, err := os.UserConfigDir()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(dir, "netbird", uiLogFileName), nil
+}
+
+// newDebugLog builds the GUI debug log, disabled when userSetLogFile is set
+// (manual --log-file override) or the config dir can't be resolved.
+func newDebugLog(userSetLogFile bool) *guilog.DebugLog {
+	path, err := uiLogPath()
+	if err != nil {
+		log.Warnf("resolve GUI log path: %v; GUI file logging disabled", err)
+		return guilog.NewDebugLog("", false)
+	}
+	return guilog.NewDebugLog(path, !userSetLogFile)
+}