feat: cli arg for file permission of socket (#4923)

test/unit/node/app.test.ts

@@ -107,6 +107,18 @@ describe("createApp", () => {
     app.dispose()
   })
 
+  it("should change the file mode of a socket", async () => {
+    const defaultArgs = await setDefaults({
+      socket: tmpFilePath,
+      "socket-mode": "777",
+    })
+
+    const app = await createApp(defaultArgs)
+
+    expect((await promises.stat(tmpFilePath)).mode & 0o777).toBe(0o777)
+    app.dispose()
+  })
+
   it("should create an https server if args.cert exists", async () => {
     const testCertificate = await generateCertificate("localhost")
     const cert = new OptionalString(testCertificate.cert)