[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/const.go

@@ -1,15 +0,0 @@
-package main
-
-const (
-	allowSSHMenuDescr          = "Allow SSH connections"
-	autoConnectMenuDescr       = "Connect automatically when the service starts"
-	quantumResistanceMenuDescr = "Enable post-quantum security via Rosenpass"
-	blockInboundMenuDescr      = "Block inbound connections to the local machine and routed networks"
-	notificationsMenuDescr     = "Enable notifications"
-	advancedSettingsMenuDescr  = "Advanced settings of the application"
-	debugBundleMenuDescr       = "Create and open debug information bundle"
-	disabledMenuDescr          = ""
-	networksMenuDescr          = "Open the networks management window"
-	latestVersionMenuDescr     = "Download latest version"
-	quitMenuDescr              = "Quit the client app"
-)