Changelog

Unreleased

wrapPackage: when passing explicit args, "$@" is no longer appended automatically by the wrapper template. If you pass custom args and want passthrough, include "$@" in your args list. The default args (generated from flags) still includes "$@".
flagSeparator default changed from " " to null. The old " " default was misleading: it produced separate argv entries, not a space-joined arg. null now means separate argv entries. If you were explicitly passing flagSeparator = " " to get separate args, remove it (or change to null).

lib/modules/command.nix: base module with shared command spec (args, env, hooks, exePath) used by both wrapper and systemd outputs.
lib/modules/flags.nix: flags module with per-flag ordering via { value, order } submodules. Default order is 1000. Reading config.flags returns clean values (order is transparent).
wrapper.nix injects "$@" into args at order 1001, controllable via the ordering system.
outputs.wrapper as the canonical output path (config.wrapper is a backward-compatible alias).