refactor: centralize update targets and extension guardrails

test/scripts/pnpm-runner.test.ts

@@ -1,5 +1,5 @@
 import { describe, expect, it } from "vitest";
-import { resolvePnpmRunner } from "../../scripts/pnpm-runner.mjs";
+import { createPnpmRunnerSpawnSpec, resolvePnpmRunner } from "../../scripts/pnpm-runner.mjs";
 
 describe("resolvePnpmRunner", () => {
   it("uses npm_execpath when it points to pnpm", () => {
@@ -67,4 +67,25 @@ describe("resolvePnpmRunner", () => {
       windowsVerbatimArguments: true,
     });
   });
+
+  it("builds a shared spawn spec with inherited stdio and env overrides", () => {
+    const env = { PATH: "/custom/bin", FOO: "bar" };
+    expect(
+      createPnpmRunnerSpawnSpec({
+        npmExecPath: "",
+        pnpmArgs: ["exec", "vitest", "run"],
+        platform: "linux",
+        env,
+      }),
+    ).toEqual({
+      command: "pnpm",
+      args: ["exec", "vitest", "run"],
+      options: {
+        stdio: "inherit",
+        env,
+        shell: false,
+        windowsVerbatimArguments: undefined,
+      },
+    });
+  });
 });