fix: include response body in publish_collectible auth error

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "rbx-upload"
-version = "0.2.8"
+version = "0.2.9"
 description = "Roblox asset upload client"
 requires-python = ">=3.13"
 dependencies = [

src/rbx_upload/client.py

@@ -297,7 +297,7 @@ class RobloxClient:
         if response.status_code == 429:
             raise RateLimitError("Rate limit hit during collectible publish.")
         if response.status_code in (401, 403):
-            raise AuthError("Not authorized to publish this collectible.")
+            raise AuthError(f"Not authorized to publish this collectible ({response.status_code}): {response.text}")
 
         response.raise_for_status()
         data = response.json()