Issue
Title: [v2] Validate CloudTrail log files don't have appended data
Description
Internal: D454429470
When validating CloudTrail logs, assert that there's no unused/appended data after the first gzip member is fully consumed and decompressed.
Task
Modify the repository so that the issue described above is resolved. The repository is checked out at base commit f2892543f2b9. Edit files in place; the verifier captures your changes via git diff and scores them against an oracle patch using SWE-RL-style diff-similarity reward.