chore: rename marketplace to Leo Claude Marketplace

Update all references from old names to new marketplace identity:
- support-claude-mktplace → leo-claude-mktplace (URLs)
- lm-claude-plugins → leo-claude-mktplace (repo name)
- Claude Code Marketplace → Leo Claude Marketplace (display name)

Files updated:
- Core docs (CLAUDE.md, README.md, CHANGELOG.md)
- Documentation (CANONICAL-PATHS, CONFIGURATION, UPDATING, COMMANDS-CHEATSHEET)
- Marketplace manifest and all 9 plugin.json files
- Plugin READMEs and MCP server READMEs
- Setup script and label taxonomy reference

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

docs/UPDATING.md

@@ -1,4 +1,4 @@
-# Updating support-claude-mktplace
+# Updating Leo Claude Marketplace
 
 This guide covers how to update your local installation when new versions are released.
 
@@ -6,7 +6,7 @@ This guide covers how to update your local installation when new versions are re
 
 ```bash
 # 1. Pull latest changes
-cd /path/to/support-claude-mktplace
+cd /path/to/leo-claude-mktplace
 git pull origin main
 
 # 2. Run post-update script