chore(models): regenerate against the pinned 2026-08-25 UCP schema

Regenerates via ./generate_models.sh 2026-08-25 (the same command the
model-drift CI job runs) to pick up the postprocessing fix in the
prior commit. Three files change, all in the location_serves family:
LocationServes, LocationServesCreateRequest and
LocationServesUpdateRequest each gain an _enforce_max_properties
validator alongside their existing _enforce_min_properties one.

Verified:
- Full suite: 100 tests, 0 failures, 4 documented skips (both new
  semantic tests from the RED commit now pass).
- Double-regen: ran generate_models.sh 2026-08-25 twice; diff -rq
  between both outputs (excluding __pycache__) is empty.
- Kill-test: reverted postprocess_models.py to its pre-fix state,
  regenerated, reinstalled -- the same 2 failures + 6 errors from the
  RED commit reappeared verbatim. Restored the fix and regenerated
  again to confirm the suite returns to green.
- pre-commit run on the changed files: clean.

Not committed: README.md, which ruff format also reformats as a
pre-existing docstring-code-block spacing drift in main, unrelated to
this fix (see the equivalent note on the jwk-conditional-rules branch).

Author: katyalai

src/ucp_sdk/models/schemas/common/types/location_serves.py

@@ -84,3 +84,14 @@ def _enforce_min_properties(self):
                 "At least 1 property must be provided (schema minProperties=1)"
             )
         return self
+
+    @model_validator(mode="after")
+    def _enforce_max_properties(self):
+        """JSON Schema maxProperties: allow at most 1
+        provided property."""
+        provided = self.model_fields_set | set(self.model_extra or {})
+        if len(provided) > 1:
+            raise ValueError(
+                "At most 1 property may be provided (schema maxProperties=1)"
+            )
+        return self

src/ucp_sdk/models/schemas/common/types/location_serves_create_request.py

@@ -84,3 +84,14 @@ def _enforce_min_properties(self):
                 "At least 1 property must be provided (schema minProperties=1)"
             )
         return self
+
+    @model_validator(mode="after")
+    def _enforce_max_properties(self):
+        """JSON Schema maxProperties: allow at most 1
+        provided property."""
+        provided = self.model_fields_set | set(self.model_extra or {})
+        if len(provided) > 1:
+            raise ValueError(
+                "At most 1 property may be provided (schema maxProperties=1)"
+            )
+        return self

src/ucp_sdk/models/schemas/common/types/location_serves_update_request.py

@@ -84,3 +84,14 @@ def _enforce_min_properties(self):
                 "At least 1 property must be provided (schema minProperties=1)"
             )
         return self
+
+    @model_validator(mode="after")
+    def _enforce_max_properties(self):
+        """JSON Schema maxProperties: allow at most 1
+        provided property."""
+        provided = self.model_fields_set | set(self.model_extra or {})
+        if len(provided) > 1:
+            raise ValueError(
+                "At most 1 property may be provided (schema maxProperties=1)"
+            )
+        return self