feat: integrate Learning Center MCP for documentation intelligence

- Add postman-docs MCP server to plugin.json (v1.1.0)
- Update command instructions to use docs MCP for "how do I" questions
- Update README with documentation intelligence section
- Plugin now combines operations (scripts) + knowledge (docs MCP)

This turns AI into a true Postman expert that can both execute
and explain. Jon Konrath's Learning Center MCP endpoint:
https://learning.postman.com/_mcp/server

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "postman-skill",
-  "version": "1.0.0",
-  "description": "Postman API lifecycle management for Claude Code. Manage collections, environments, monitors, mocks, and analyze APIs for agent-readiness.",
+  "version": "1.1.0",
+  "description": "Postman API lifecycle management for Claude Code. Manage collections, environments, monitors, mocks, and analyze APIs for agent-readiness. Includes Learning Center docs integration.",
   "author": "Sterling Chin",
   "repository": "https://github.com/sterlingchin/postman-slash-command",
   "license": "MIT",
@@ -13,11 +13,20 @@
     "mocks",
     "monitors",
     "agent-ready",
-    "clara"
+    "clara",
+    "mcp",
+    "documentation"
   ],
   "components": {
     "commands": ["postman"]
   },
+  "mcpServers": {
+    "postman-docs": {
+      "type": "http",
+      "url": "https://learning.postman.com/_mcp/server",
+      "description": "Postman Learning Center documentation - how-to guides, best practices, feature docs"
+    }
+  },
   "dependencies": {
     "python": ">=3.7"
   }