feat: NetUP via agent — proxy HTTP requests through Windows workstation

- Migration 044: add connection_type + agent_workstation_id to netup_settings
- Backend: netupReqViaCfg routes requests via agent WebSocket when connection_type=agent
- Agent: add netup_request command handler (proxies HTTP to local NetUP server)
- TvWelcomePage: add connection mode toggle (direct / via agent) + workstation selector
- Hint changes: URL placeholder shows local IP when agent mode selected

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/lib/api.ts

@@ -546,10 +546,10 @@ export const api = {
   // ── NetUP IPTV ────────────────────────────────────────────────────────────
   netup: {
     getSettings: (slug: string) =>
-      req<{ serverUrl: string; username: string; password: string; defaultLanguage: string; enabled: boolean; tlToken: string }>(
+      req<{ serverUrl: string; username: string; password: string; defaultLanguage: string; enabled: boolean; tlToken: string; connectionType: string; agentWorkstationId: string | null }>(
         'GET', `/api/hotels/${slug}/netup/settings`),
 
-    saveSettings: (slug: string, data: { server_url: string; username: string; password?: string; default_language: string; enabled: boolean; tl_token: string }) =>
+    saveSettings: (slug: string, data: { server_url: string; username: string; password?: string; default_language: string; enabled: boolean; tl_token: string; connection_type: string; agent_workstation_id: string | null }) =>
       req<{ ok: boolean }>('PATCH', `/api/hotels/${slug}/netup/settings`, data),
 
     testConnection: (slug: string) =>