fix(seer): Guard token creation against None/AnonymousUser

create_explorer_api_token expects a real user, but self.user can be
None or AnonymousUser. Skip token creation in those cases.

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

Author: azulus

src/sentry/seer/explorer/client.py

@@ -273,6 +273,8 @@ def start_run(
         user_auth_token = (
             create_explorer_api_token(self.user, self.organization)
             if self.enable_code_mode_tools
+            and self.user
+            and not isinstance(self.user, AnonymousUser)
             else None
         )
 
@@ -380,6 +382,8 @@ def continue_run(
         user_auth_token = (
             create_explorer_api_token(self.user, self.organization)
             if self.enable_code_mode_tools
+            and self.user
+            and not isinstance(self.user, AnonymousUser)
             else None
         )