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>

scripts/start_netx.ps1

@@ -147,6 +147,8 @@ function Show-LogTail {
 function Test-NetxApiListening {
     param([string]$HostName, [int]$LocalPort, [int]$WaitSec = 45)
     $deadline = (Get-Date).AddSeconds($WaitSec)
+    # Wildcard binds are not connectable on Windows; probe via loopback.
+    if ($HostName -in @("0.0.0.0", "::", "[::]", "*")) { $HostName = "127.0.0.1" }
     $healthUrl = "http://${HostName}:${LocalPort}/health"
     while ((Get-Date) -lt $deadline) {
         try {