refactor: auto start apps on login via xdg-autostart (#242)

Signed-off-by: Ryan Yin <xiaoyin_c@qq.com>

home/linux/gui/base/xdg/autostart.nix

@@ -0,0 +1,23 @@
+{ pkgs, lib, ... }:
+{
+  # XDG autostart entries - ensures apps start after portal services are ready
+  xdg.autostart.enable = true;
+  # This fixes nixpak sandboxed apps (like firefox) accessing mapped folders correctly
+  xdg.autostart.entries = [
+    "${pkgs.foot}/share/applications/foot.desktop"
+    "${pkgs.alacritty}/share/applications/Alacritty.desktop"
+    "${pkgs.ghostty}/share/applications/com.mitchellh.ghostty.desktop"
+
+    "${pkgs.clash-verge-rev}/share/applications/clash-verge.desktop"
+
+    # nixpaks
+    "${pkgs.nixpaks.firefox}/share/applications/org.mozilla.firefox.desktop"
+    "${pkgs.nixpaks.telegram-desktop}/share/applications/org.telegram.desktop.desktop"
+  ]
+  ++ (
+    if pkgs.stdenv.isx86_64 then
+      [ "${pkgs.google-chrome}/share/applications/google-chrome.desktop" ]
+    else
+      [ "${pkgs.chromium}/share/applications/chromium-browser.desktop" ]
+  );
+}