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/constants.js

@@ -0,0 +1,21 @@
+module.exports = {
+  ROOT_GITHUB: 'https://github.com/zapier/zapier-platform',
+  DOCS_PATH: 'docs/build/schema.md',
+  DOC_URL_TEMPLATE:
+    'https://github.com/zapier/zapier-platform/blob/zapier-platform-cli%40<%= version %>/packages/schema/docs/build/schema.md<%= anchor %>',
+  SKIP_KEY: '_skipTest',
+  // the following pairs of keys can't be used together in PlainFieldSchema
+  // they're stored here because they're used in a few places
+  INCOMPATIBLE_FIELD_SCHEMA_KEYS: [
+    ['children', 'list'], // This is actually a Feature Request (https://github.com/zapier/zapier-platform-cli/issues/115)
+    ['children', 'dict'], // dict is ignored
+    ['children', 'type'], // type is ignored
+    ['children', 'placeholder'], // placeholder is ignored
+    ['children', 'helpText'], // helpText is ignored
+    ['children', 'default'], // default is ignored
+    ['dict', 'list'], // Use only one or the other
+    ['dynamic', 'dict'], // dict is ignored
+    ['dynamic', 'choices'], // choices are ignored
+  ],
+  FIELD_SCHEMA_BOOLEANS: new Set(['dict', 'list']),
+};