Function run_polling_watch_loop 

pub(crate) fn run_polling_watch_loop(
    store: &mut AtlasStore,
    plan: &ScanRuntimePlan,
    poll_seconds: u64,
    max_cycles: usize,
    symbol_options: &SymbolBuildOptions,
    fallback_reason: Option<String>,
) -> Result<WatchReport, CliError>

Run the portable polling watcher fallback loop.