bench eval create should expose --max-retries alias

[bingran-you]

Mirrors Linear ENG-169: https://linear.app/benchflow/issue/ENG-169/cli-expose-max-retries-on-bench-eval-create

Problem

bench eval create supports retry control via YAML max_retries and CLI --retry-attempts, but users naturally try --max-retries and get No such option.

Expected

--max-retries should be a first-class CLI alias for the current retry-attempt override and work for both --tasks-dir and --config eval runs. Passing both aliases should fail fast instead of silently choosing one.

Current fix path

Daily scan 2026-07-11 confirmed this is a narrow BenchFlow CLI issue. A focused PR is being prepared.

[bingran-you]

Daily scan follow-up (2026-07-12): #918 is the active BenchFlow fix PR for this issue and is currently green on GitHub checks.

Current state:

• PR fix(eval): clean Linear issue UX paths #918 closes this issue and adds the bench eval create --max-retries alias behavior with conflict validation.
• CI is green on head ccb8284cd62e37ab898393fd74e07bbd6b805238 (test, pip-audit, manifest-parity, integration-light / rollout-smoke; integration-scope plan/matrix skipped as expected for this scope).
• No additional BenchFlow code change started from today's scan; remaining gate is human review/merge of fix(eval): clean Linear issue UX paths #918.

Labels updated: added reviewing while the fix PR is open.