refactor: key capabilities on href instead of rt

OCF rt is a schema category shared by many unrelated resources.
The stable unique resource address is the href. Update Capability,
discovery, common capabilities, tests, and plan accordingly.

tests/test_capability.py

@@ -3,7 +3,7 @@ from samsung_appliance.registry.entities import BinarySensorDesc
 
 
 def test_capability_defaults():
-    c = Capability(rt='x.com.samsung.da.kidsLock',
+    c = Capability(href='/kidslock/vs/0',
                    entities=(BinarySensorDesc(key='child_lock', field='x.com.samsung.da.kidsLock'),))
     assert c.poll_tier == 'warm'
     assert c.observe is True
@@ -12,9 +12,9 @@ def test_capability_defaults():
 
 
 def test_capability_is_frozen():
-    c = Capability(rt='x', entities=())
+    c = Capability(href='/kidslock/vs/0', entities=())
     try:
-        c.rt = 'y'
+        c.href = '/other/vs/0'
     except Exception:
         return
     raise AssertionError("expected frozen dataclass")