Add IPv6 sensor to fritz component (#75708)

* Add IPv6 sensor to fritz component

* Cast return type to string

* Make ipv6 sensor suitable

* simplify cast to str

* use extisting property

Co-authored-by: chemelli74 <simone.chemelli@gmail.com>
Co-authored-by: mib1185 <mail@mib85.de>

homeassistant/components/fritz/common.py

@@ -663,6 +663,14 @@ class AvmWrapper(FritzBoxTools):
             partial(self.get_wan_link_properties)
         )
 
+    async def async_ipv6_active(self) -> bool:
+        """Check ip an ipv6 is active on the WAn interface."""
+
+        def wrap_external_ipv6() -> str:
+            return str(self.fritz_status.external_ipv6)
+
+        return bool(await self.hass.async_add_executor_job(wrap_external_ipv6))
+
     async def async_get_connection_info(self) -> ConnectionInfo:
         """Return ConnectionInfo data."""
 
@@ -671,6 +679,7 @@ class AvmWrapper(FritzBoxTools):
             connection=link_properties.get("NewWANAccessType", "").lower(),
             mesh_role=self.mesh_role,
             wan_enabled=self.device_is_router,
+            ipv6_active=await self.async_ipv6_active(),
         )
         _LOGGER.debug(
             "ConnectionInfo for FritzBox %s: %s",
@@ -1011,3 +1020,4 @@ class ConnectionInfo:
     connection: str
     mesh_role: MeshRoles
     wan_enabled: bool
+    ipv6_active: bool