Keep the current precedence and migration semantics intact while converting the remaining internal async helpers (`loadState`, `mergeFile`, `loadFile`, `load`) to `Effect.gen(...)` / `Effect.fn(...)`.
- [ ]`cli/cmd/tui/config/tui.ts` callers - once the internal service is stable, migrate plain async callers to use `TuiConfig.Service` directly where that actually simplifies the code.
- [ ]`config/config.ts` - switch internal config loading from `Effect.promise(() => ConfigPaths.*(...))` to `yield* paths.*(...)` once the service exists.
- [ ]`cli/cmd/tui/config/tui.ts` - switch TUI config loading from async `ConfigPaths.*` wrappers to the `ConfigPaths.Service` once that service exists.
- [ ]`cli/cmd/tui/config/tui-migrate.ts` - decide whether to leave this as a plain async module using wrapper functions or effectify it fully after `ConfigPaths.Service` lands.