Inspect and compare feature flag states across React release channels.

• ›View all flags across channels (www, www-modern, canary, next, experimental, rn variants) or compare specific channels with --diff
• ›Output formats include default table view, CSV export, and cleanup status grouping
• ›Flag states indicated by symbols: enabled (✅), disabled (❌), variant testing (🧪), profiling-only (📊)
• ›Common pitfall: __VARIANT__ flags are tested in both states on www; use --diff to spot meaningful