test: assert hybrid CLI flags appear in the built JAR --help

Problem

verification/ci-verify.py registers hybrid CLI options in HYBRID_OPTIONS, which exempts them from check_option_coverage(). That is a self-granted behavioral exemption: the gate can be green while the JVM silently ignores the flag (e.g., a flag registered in options.json but never wired in CLIOptions). The feature branch for --hybrid-chunk-size relied on this exemption.

Suggested fix

For each option in HYBRID_OPTIONS, run a cheap real-CLI smoke (or at minimum assert the flag appears in the built JAR's --help output). Fail closed when options.json is missing or a registered option is absent from the live CLI.

Severity: P2 | Confidence: 75 | Reviewer(s): adversarial