fix: correct plugin source path format

- Change "." to "./" for valid source path

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

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

Author: auge2u

.claude-plugin/marketplace.json

@@ -11,7 +11,7 @@
   "plugins": [
     {
       "name": "claude-dev-kit",
-      "source": ".",
+      "source": "./",
       "description": "Comprehensive developer environment toolkit for Claude Code. Includes shell setup (zsh, powerlevel10k), editor config (VS Code/Cursor), git workflows, project templates, quality gates, and context management.",
       "version": "1.0.0",
       "author": {