Merge main into feat/add-python-3.12

Bringing in URL trailing slash pattern fixes from main branch.

This merge includes:
- Client collection path updates for circles and assignments
- Ensures consistency with server-side URL patterns

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

Author: JS

campus_python/api/v1/assignments.py

@@ -10,7 +10,7 @@
 
 class Assignments(ResourceCollection):
     """Campus API Assignments resource."""
-    path = "assignments"
+    path = "assignments/"
 
     def __getitem__(self, assignment_id: str) -> "Assignments.Assignment":
         """Get a specific assignment resource by ID."""

campus_python/api/v1/circles.py

@@ -10,7 +10,7 @@
 
 class Circles(ResourceCollection):
     """Campus API Circles resource."""
-    path = "circles"
+    path = "circles/"
 
     def __getitem__(self, circle_id: str) -> "Circles.Circle":
         """Get a specific circle resource by ID."""