v2.0.7: security hardening, config sync, cleanup

- 6 new security audits (technical_debt_8 through 12)
- SNI rotation pool per session (5 sites)
- vless_ip pinned to hardcoded server IP
- TLS cert validation restored (domain-based)
- Swarm monitoring removed from public domain
- Xray routing blocks abuse ports (SMTP, NetBIOS, SSDP)
- flow: xtls-rprx-vision in add_vless_client
- TimerBox shows Connecting/Syncing spinner
- Outbound port blocking in Xray config
- Cleaned up comments, synced config templates

lib/components/sidebar_drawer.dart

@@ -108,7 +108,7 @@ class SidebarDrawer extends StatelessWidget {
 
             const Padding(
               padding: EdgeInsets.all(20),
-              child: Text('ReVoltVPN · v1.0.7', textAlign: TextAlign.center,
+              child: Text('ReVoltVPN · v2.0.7', textAlign: TextAlign.center,
                 style: TextStyle(color: AppColors.slate, fontSize: 11, letterSpacing: 1),
               ),
             ),