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/v18.2.0.md

@@ -0,0 +1,29 @@
+> ## 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.
+
+# What's changed in v18.2.0
+
+> invoke command supports function-based choices, stashing returns a better error message
+
+*Released: 2026-02-18*
+
+The main change in this release is to support function-based choices in the `invoke` command, which will allow developers to test perform-based dynamic dropdowns.
+
+## cli
+
+* 🎉 `zapier-platform invoke` now supports function-based choices ([#1237](https://github.com/zapier/zapier-platform/pull/1237))
+
+## core
+
+* 🐛 If we attempt to stash a large response but it's bigger than the max limit, throw a descriptive error with the actual size and the limit ([#1238](https://github.com/zapier/zapier-platform/pull/1238))
+* 🔨 Add an environment variable to allow suppressing cleaning up env vars ([#1242](https://github.com/zapier/zapier-platform/pull/1242))
+
+## schema
+
+None!
+
+## misc
+
+* 🔨 CI: Use `environment` to publish ([#1239](https://github.com/zapier/zapier-platform/pull/1239))
+* 🔨 CI: Automate the boilerplate upload ([#1240](https://github.com/zapier/zapier-platform/pull/1240))