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/side-channel/.eslintrc

@@ -0,0 +1,12 @@
+{
+	"root": true,
+
+	"extends": "@ljharb",
+
+	"rules": {
+		"id-length": 0,
+		"max-lines-per-function": 0,
+		"multiline-comment-style": 1,
+		"new-cap": [2, { "capIsNewExceptions": ["GetIntrinsic"] }],
+	},
+}