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.

research/zapier/raw/docs/integrations/news/2026/migrations-same-major-version.md

@@ -0,0 +1,15 @@
+> ## Documentation Index
+> Fetch the complete documentation index at: https://docs.zapier.com/llms.txt
+> Use this file to discover all available pages before exploring further.
+
+# User migrations must stay within the same major version
+
+> The Platform UI and CLI now block migrating users when the source and target integration versions differ in their [semantic major version](/integrations/manage/versions#version-numbering)—for example, you cannot migrate from `1.x.x` to `2.x.x`.
+
+*Effective: 2026-02-26*
+
+## Same-major-version migrations only
+
+* Migrations are only allowed when the **from** and **to** versions share the same major number (e.g. `1.0.0` → `1.0.1`, or `2.1.0` → `2.2.0`).
+* Cross-major moves (e.g. `1.5.0` → `2.0.0`) are blocked in both the [Platform UI](https://zapier.com/app/developer) and via [`zapier-platform migrate`](https://github.com/zapier/zapier-platform/blob/main/packages/cli/docs/cli.md#migrate). This aligns with long-standing guidance; major releases include [breaking changes](/integrations/manage/planning-changes), so users should [update Zap workflows manually](https://help.zapier.com/hc/en-us/articles/18755649454989-App-versions-in-Zapier) or you should use [deprecation](/integrations/manage/versions#deprecating-versions) instead of migration.
+* Details and workflow are in [Migrate users to a new version](/integrations/manage/migrate).