Bundle brainstorm server dependencies instead of requiring npm install

Vendor node_modules into the repo so the brainstorm server works
immediately on fresh plugin installs without needing npm at runtime.

skills/brainstorming/scripts/node_modules/dunder-proto/get.d.ts

@@ -0,0 +1,5 @@
+declare function getDunderProto(target: {}): object | null;
+
+declare const x: false | typeof getDunderProto;
+
+export = x;