New: Runtime Beta Mode

Runtime Beta Mode (--betamode / -z)

• Introduces --betamode (-z) – a runtime flag to enable experimental beta rules during scan.
• Default: Disabled (opt-out) – ensures stable, production-safe scans.
• CLI override: --betamode forces beta rules even if config says false.
• Config support: betamode: true in .flow-scanner.yml enables by default.
• Precedence: CLI flag > config file > default (false)
• Fully backward compatible – configs without betamode default to false.
• No code changes needed – core scanner automatically includes getBetaRules() when enabled.