[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/frontend/src/hooks/useAutoSizeWindow.ts

@@ -0,0 +1,60 @@
+import { useLayoutEffect, useRef } from "react";
+import { Window } from "@wailsio/runtime";
+import i18next from "@/lib/i18n";
+import { isLinux } from "@/lib/platform";
+
+// Sizes the current Wails window to the measured content height (keeping `width`),
+// then shows it. Re-applies on content resize and language change.
+export function useAutoSizeWindow<T extends HTMLElement>(width: number, ready: boolean = true) {
+    const ref = useRef<T | null>(null);
+    useLayoutEffect(() => {
+        const el = ref.current;
+        if (!el) return;
+        let shown = false;
+        let raf1 = 0;
+        let raf2 = 0;
+        const showOnce = () => {
+            if (shown) return;
+            shown = true;
+            Window.Show().catch(() => {});
+            Window.Focus().catch(() => {});
+        };
+        const apply = async () => {
+            if (!ready) return;
+            const h = Math.ceil(el.getBoundingClientRect().height);
+            if (h <= 0) return;
+            try {
+                // Window.SetSize takes the frame size, so add the OS title-bar height or content clips.
+                const frame = await Window.Size();
+                const targetH = h + Math.max(0, frame.height - window.innerHeight);
+                // Linux: SetSize no-ops on a mapped non-resizable window (X11), so pin via min/max instead.
+                if (isLinux()) {
+                    await Window.SetMinSize(width, targetH);
+                    await Window.SetMaxSize(width, targetH);
+                }
+                await Window.SetSize(width, targetH);
+                showOnce();
+            } catch {
+                // window gone / not ready — ignore
+            }
+        };
+        const scheduleApply = () => {
+            cancelAnimationFrame(raf1);
+            cancelAnimationFrame(raf2);
+            raf1 = requestAnimationFrame(() => {
+                raf2 = requestAnimationFrame(apply);
+            });
+        };
+        apply();
+        const ro = new ResizeObserver(apply);
+        ro.observe(el);
+        i18next.on("languageChanged", scheduleApply);
+        return () => {
+            ro.disconnect();
+            cancelAnimationFrame(raf1);
+            cancelAnimationFrame(raf2);
+            i18next.off("languageChanged", scheduleApply);
+        };
+    }, [width, ready]);
+    return ref;
+}