Provider Test Patterns

This gives Claude the patterns for writing Terraform provider acceptance tests with terraform-plugin-testing and the Plugin Framework. It covers the test lifecycle (plan, apply, refresh, final plan check), modern ConfigStateChecks with statecheck implementations versus legacy TestCheckFunc patterns, import testing with ImportStateKind, sweepers, and ephemeral resource testing. The source includes actual code examples for test structure, config helpers with numbered format verbs, and scenario patterns like basic/update combinations and disappears tests. Use it when you're writing or reviewing provider tests and need to know how to structure assertions, verify import behavior, or understand why CompareValue exists for cross-step checks. It assumes you know Terraform providers but need the testing framework conventions.