Remove unused build scripts, fix cisco-vpn monitor loop

- Delete init-vpn.sh, vpn-connect.sh, xstartup from build/scripts
- Change cisco-vpn monitor to background process so menu shows after connect

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/rego-tunnel/shared/cisco-vpn

@@ -634,17 +634,18 @@ start_anyconnect() {
         log WARN "Connection test: ${RED}FAILED${NC} (may need manual route on Windows)"
     fi
 
-    # Monitor and auto-reconnect
-    log INFO "Monitoring VPN connection (will auto-reconnect if disconnected)..."
-    while true; do
-        sleep 30
-        if [ -z "$(get_vpn_interface)" ]; then
-            log WARN "VPN disconnected! Reconnecting in 5 seconds..."
-            sleep 5
-            start_anyconnect "$do_auto_login"
-            return $?
-        fi
-    done
+    # Start background monitor for auto-reconnect
+    (
+        while true; do
+            sleep 30
+            if [ -z "$(get_vpn_interface)" ]; then
+                log WARN "VPN disconnected! Will reconnect on next menu action..."
+            fi
+        done
+    ) &
+
+    log INFO "VPN setup complete"
+    return 0
 }
 
 # Parse command line arguments