feat: Tor status + cleanup, Tailscale admin, marketplace install UX

- Task 0: Tor status dot (green/red) + "Cleanup Old" rotated services button
- Task 2: BTCPay already handled (opens new tab)
- Task 3: Tailscale launches https://login.tailscale.com/admin/machines in new tab
- Task 8: Marketplace install shows inline progress on card (removed banner)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

neode-ui/src/views/AppSession.vue

@@ -376,6 +376,7 @@ const EXTERNAL_URLS: Record<string, string> = {
   'syntropy-institute': 'https://syntropy.institute',
   't-zero': 'https://teeminuszero.net',
   'nostrudel': 'https://nostrudel.ninja',
+  'tailscale': 'https://login.tailscale.com/admin/machines',
 }
 
 const APP_TITLES: Record<string, string> = {
@@ -402,6 +403,7 @@ const NEW_TAB_APPS = new Set([
   'portainer',          // X-Frame-Options: deny
   'onlyoffice',         // X-Frame-Options: SAMEORIGIN
   'nginx-proxy-manager', // X-Frame-Options blocks
+  'tailscale',          // No local web UI — opens Tailscale admin
 ])
 
 const mustOpenNewTab = computed(() => NEW_TAB_APPS.has(appId.value))