fix: correct plugin installation commands in README

- Use /plugin marketplace add (not /add-marketplace)
- Use /plugin install plugin@marketplace format
- Add other useful plugin management commands

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

Author: auge2u

README.md

@@ -20,19 +20,22 @@ Both methods configure the same things - choose based on your preference.
 If you have Claude Code, install as a plugin for the full interactive experience:
 
 ```bash
-# Add the marketplace (run inside Claude Code)
-/add-marketplace auge2u/claude-dev-kit
+# Step 1: Add the marketplace (run inside Claude Code)
+/plugin marketplace add auge2u/claude-dev-kit
+
+# Step 2: Install the plugin
+/plugin install claude-dev-kit@claude-dev-kit
 ```
 
-Then start a conversation:
+Then use the skills:
 
 ```bash
 # Ask Claude to set up your environment
-claude "Set up my dev environment"
+"Set up my dev environment"
 
-# Or be specific
-claude "Setup shell with powerlevel10k"
-claude "Configure VS Code for Claude development"
+# Or invoke skills directly
+Skill: setup-claude-dev-kit
+Skill: setup-cdk-shell
 ```
 
 **What you get:**
@@ -41,6 +44,13 @@ claude "Configure VS Code for Claude development"
 - Adapts to your existing setup
 - Explains what it's doing
 
+**Other plugin commands:**
+```bash
+/plugin                              # Interactive plugin browser
+/plugin marketplace list             # List installed marketplaces
+/plugin marketplace remove claude-dev-kit  # Remove marketplace
+```
+
 ---
 
 ## Option 2: Standalone Script (No Claude Required)