feat(cli): fase 8.8 — system tray + autostart (omniroute serve --tray)

- bin/cli/tray/index.mjs: initTray/killTray/isTrayActive/isTraySupported
- bin/cli/tray/traySystray.mjs: systray2 para macOS/Linux (graceful fallback)
- bin/cli/tray/trayWindows.mjs: PowerShell NotifyIcon (sem binário extra)
- bin/cli/tray/autostart.mjs: launchd (macOS), reg (Windows), .desktop (Linux)
- bin/cli/commands/tray.mjs: subcomandos show/hide/quit
- bin/cli/commands/autostart.mjs: subcomandos enable/disable/status
- serve.mjs: flags --tray/--no-tray, integração após servidor iniciar
- i18n: chaves tray.*, autostart.*, serve.tray/no_tray em en.json e pt-BR.json
- check-env-doc-sync: DISPLAY e WAYLAND_DISPLAY adicionados ao allowlist (sinais do host OS)
- 8 testes unitários cobrindo autostart por plataforma e importação dos módulos

scripts/check/check-env-doc-sync.mjs

@@ -77,6 +77,9 @@ const IGNORE_FROM_CODE = new Set([
   "REPL_SLUG",
   "WSL_DISTRO_NAME",
   "WSL_INTEROP",
+  // X11/Wayland display server vars used by tray heuristic (isTraySupported).
+  "DISPLAY",
+  "WAYLAND_DISPLAY",
   // Aliases for documented vars handled via fallback ordering.
   "API_KEY",
   "APP_URL",