refactor: share plugin setup helpers

src/cli/root-option-forward.ts

@@ -0,0 +1,21 @@
+import { consumeRootOptionToken } from "../infra/cli-root-options.js";
+
+export function forwardConsumedCliRootOption(
+  args: readonly string[],
+  index: number,
+  out: string[],
+): number {
+  const consumedRootOption = consumeRootOptionToken(args, index);
+  if (consumedRootOption <= 0) {
+    return 0;
+  }
+
+  for (let offset = 0; offset < consumedRootOption; offset += 1) {
+    const token = args[index + offset];
+    if (token !== undefined) {
+      out.push(token);
+    }
+  }
+
+  return consumedRootOption;
+}