feat: VPN peer QR code UI, consolidate CI workflows

- Add vpn.create-peer, vpn.list-peers, vpn.remove-peer RPC methods
- Generate WireGuard config + QR code (SVG) for mobile device connection
- Add "Add Device" modal on Network page with QR scanner support
- Remove old build-iso.yml (replaced by build-iso-dev.yml)
- Remove container-tests.yml (tests run in dev workflow)
- Remove container orchestration tests from dev workflow (redundant)

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

core/archipelago/src/api/rpc/dispatcher.rs

@@ -240,6 +240,9 @@ impl RpcHandler {
             "vpn.status" => self.handle_vpn_status().await,
             "vpn.configure" => self.handle_vpn_configure(params).await,
             "vpn.disconnect" => self.handle_vpn_disconnect().await,
+            "vpn.create-peer" => self.handle_vpn_create_peer(params).await,
+            "vpn.list-peers" => self.handle_vpn_list_peers().await,
+            "vpn.remove-peer" => self.handle_vpn_remove_peer(params).await,
             "remote.setup" => self.handle_remote_setup(params).await,
 
             // Marketplace