Modernize the Windows installer, tray and runtime control; fix lifecycle bugs.

Installer: dynamic light/dark Win11 style, new brand wizard images, auto
language, exclusive run mode (tray / Windows service) plus autostart and
auto-update on the Tasks page (pre-selected from what is installed on
upgrades, untouched by silent updates), 5 localized Start Menu entries.

Tray: theme-aware rounded menu with live status, icons and status-dot tray
icon; health polled off the UI thread; Settings submenu toggles autostart
and daily updates; browser opened de-elevated via explorer.

Fixes:
- tray Stop/Start was ignored in service mode (service_run restarted the
  children) - all start/stop now goes through runtime_ctl.ps1
- logon tray task and SYSTEM service task were killed after 72h (default
  ExecutionTimeLimit); autostart was registered for the elevating account
  and opened a browser on every logon
- uninstall left the NetXTray/NetXUpdate tasks behind
- silent auto-update killed the tray without restarting it
- repair_venv.ps1 was never staged into the release
- wildcard NETX_HOST (0.0.0.0) broke health checks
- ICO frames were PNG, which System.Drawing decodes as noise; icons now
  use the current brand mark

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packaging/build_release.ps1

@@ -110,7 +110,7 @@ foreach ($name in @(
         "download_postgres.ps1", "setup_first_run.ps1", "start_netx_app.ps1",
         "stop_netx_app.ps1", "update_netx.ps1", "check_update.ps1",
         "launch_shortcut.ps1", "netx_tray.ps1", "install_autostart.ps1", "install_service.ps1",
-        "service_run.ps1", "service_lifecycle.ps1", "install_update_task.ps1", "uninstall_prepare.ps1", "uninstall_delete_data.ps1", "sign_release.ps1",
+        "service_run.ps1", "service_lifecycle.ps1", "install_update_task.ps1", "repair_venv.ps1", "runtime_ctl.ps1", "uninstall_prepare.ps1", "uninstall_delete_data.ps1", "sign_release.ps1",
         "build_release.ps1", "publish_release.ps1", "publish_forgejo_release.ps1", "README.md", "manifest.example.json"
     )) {
     $src = Join-Path $PSScriptRoot $name