Fix: read WG server IP and subnet from live API instead of hardcoding 10.0.0.x

test_wg_connect_and_ping_server and the connected_peer fixture hardcoded
10.0.0.1 / 10.0.0.0/24 as the server VPN address. This breaks when the
server uses a different subnet (e.g. pic1 uses 10.0.1.1/24). Now both
read 'address' from /api/wireguard/status at session start and pass the
live server_ip / server_network through wg_server_info and connected_peer.

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

tests/e2e/wg/test_wg_basic.py

@@ -7,8 +7,9 @@ pytestmark = pytest.mark.wg
 def test_wg_connect_and_ping_server(connected_peer):
     """Scenario 25+26: create peer, connect, ping server VPN IP."""
     iface = connected_peer['iface']
+    server_ip = connected_peer.get('server_ip', '10.0.0.1')
     assert iface.up, "WireGuard interface should be up"
-    assert iface.is_connected('10.0.0.1'), "Server VPN IP 10.0.0.1 should be reachable via WireGuard"
+    assert iface.is_connected(server_ip), f"Server VPN IP {server_ip} should be reachable via WireGuard"
 
 
 def test_wg_peer_has_assigned_ip(connected_peer):
@@ -21,8 +22,9 @@ def test_wg_peer_has_assigned_ip(connected_peer):
 def test_wg_disconnect_removes_route(connected_peer):
     """Scenario 29: after disconnect, VPN IP is not reachable."""
     iface = connected_peer['iface']
+    server_ip = connected_peer.get('server_ip', '10.0.0.1')
     iface.bring_down()
-    result = subprocess.run(['ping', '-c', '1', '-W', '2', '10.0.0.1'],
+    result = subprocess.run(['ping', '-c', '1', '-W', '2', server_ip],
                             capture_output=True, timeout=5)
     # After disconnect, ping should fail
     assert result.returncode != 0, "VPN IP should not be reachable after disconnect"