add(plugin): terraform — HashiCorp infrastructure-as-code

Adapted from PR #14 by @gautambaghel (HashiCorp).
Original: https://github.com/anthropics/claude-plugins-official/pull/14

external_plugins/terraform/.claude-plugin/plugin.json

@@ -0,0 +1,7 @@
+{
+  "name": "terraform",
+  "description": "The Terraform MCP Server provides seamless integration with Terraform ecosystem, enabling advanced automation and interaction capabilities for Infrastructure as Code (IaC) development.",
+  "author": {
+    "name": "HashiCorp"
+  }
+}