Skeleton setup for postgres-skills repo

Mirrors the agent-skills repo structure with a placeholder
postgres-best-practices skill and one example reference file.

Co-authored-by: Cursor <cursoragent@cursor.com>

.claude-plugin/plugin.json

@@ -0,0 +1,14 @@
+{
+  "name": "postgres-skills",
+  "version": "1.0.0",
+  "description": "Postgres best practices and guidelines for coding agents.",
+  "author": {
+    "name": "Neon",
+    "url": "https://neon.tech"
+  },
+  "homepage": "https://github.com/neondatabase/postgres-skills",
+  "repository": "https://github.com/neondatabase/postgres-skills",
+  "license": "Apache-2.0",
+  "keywords": ["postgres", "postgresql", "best-practices", "database"],
+  "skills": "./skills/"
+}