refactor: discover api endpoints dynamically

gallagher command centre makes available a set of hrefs that should be
dynamically references as opposed to statically referencing api endpoints
this is the start of the change to do so. as part of this it's recommended to

- drop the root api endpoint query to be a privat endpoint
- the utils package to be renamed as core
- move the discovery contant outside of the APIEndpoint class

REFS #5

gallagher/cc/alarms/items.py

@@ -18,7 +18,7 @@ class ItemsTypes(APIEndpoint):
     """
 
     __config__ = EndpointConfig(
-        endpoint="items/types",
+        endpoint=cls.paths.features.alarms.alarms.href,
         dto_list=ItemTypesResponse,
     )
 

gallagher/cc/utils.py

@@ -1,12 +1,25 @@
 """ Utilities for the Gallagher Command Centre API
 
+This package provides a set of utilities that are used that each endpoint
+uses to communicate with the Gallagher Command Centre API.
+
+Every endpoint inherits from the APIEndpoint class and must define
+a configuration that is assigned to the variable __config__.
+
+The endpoint variable in the EndpointConfig should be assigned to a reference
+to the endpoint in the DiscoveryResponse object. When initialised the
+endpoint will be assigned to None but will self heal as part of 
+the bootstrapping process.
 """
 from typing import Optional
 from dataclasses import dataclass
 
 import httpx
 
-from ..dto.discover import DiscoverResponse
+from ..dto.discover import (
+    DiscoveryResponse,
+    FeaturesDetail,
+)
 
 
 def check_api_key_format(api_key):
@@ -93,7 +106,10 @@ class APIEndpoint():
     # to access the endpoint then the library will throw an exception
     #
     # This value is memoized and should perform
-    paths = DiscoverResponse()
+    paths = DiscoveryResponse(
+        version="0.0.0",  # Indicates that it's not been discovered
+        features=FeaturesDetail()
+    )
 
     # This must be overridden by each child class that inherits
     # from this base class.
@@ -107,7 +123,13 @@ def _discover(cls):
         on the first operation that is accessed, subsequent calls
         will return the cached result.
         """
-        pass
+        # Auto-discovery of the API endpoints, this will
+        # be called as part of the bootstrapping process
+        from ..cc import (
+            APIFeatureDiscovery
+        )
+
+        cls.paths = APIFeatureDiscovery.list()
 
     @classmethod
     def list(cls, skip=0):

gallagher/dto/discover.py

@@ -4,7 +4,10 @@
 
 """
 
-from typing import Optional
+from typing import (
+    Annotated,
+    Optional,
+)
 
 from .utils import (
     AppBaseModel,
@@ -228,8 +231,9 @@ class DiscoveryResponse(
     the API client can work with the server.  
     """
 
-    version: str
-    features: FeaturesDetail
+    version: Annotated[str, "The version of the server"]
+    features: Annotated[FeaturesDetail,
+                        "A list of features available on the server"]
 
     @property
     def get_sem_ver(self):