Milestone 0: import zappier billing, Verae middleware, and Zapier research

Compose-ready workspace: packages/zappier (rate card, portal, Stripe),
packages/verae-zapier-middleware (timestamp + NATS), packages/verae-zapier
(CLI app), vendor/zapier-platform, and research/zapier vendor corpus.

Gate 0 structure checks pass. Product code and research are not yet wired.

vendor/zapier-platform/packages/schema/lib/schemas/InputFieldsSchema.js

@@ -0,0 +1,20 @@
+'use strict';
+
+const makeSchema = require('../utils/makeSchema');
+
+const PlainInputFieldSchema = require('./PlainInputFieldSchema');
+const FunctionSchema = require('./FunctionSchema');
+
+module.exports = makeSchema(
+  {
+    id: '/InputFieldsSchema',
+    description: 'An array or collection of input fields.',
+    type: 'array',
+    items: {
+      oneOf: [{ $ref: PlainInputFieldSchema.id }, { $ref: FunctionSchema.id }],
+    },
+    examples: [[{ key: 'abc' }]],
+    antiExamples: [{ example: {}, reason: 'Must be an array' }],
+  },
+  [PlainInputFieldSchema, FunctionSchema],
+);