Bump version to 2.8.0 for julik-frontend-races-reviewer agent

- Add CHANGELOG entry for new frontend race condition reviewer
- Update agent count from 23 to 24 in plugin.json and marketplace.json

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

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

plugins/compounding-engineering/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "compounding-engineering",
-  "version": "2.7.0",
-  "description": "AI-powered development tools. 23 agents, 16 commands, 11 skills, 2 MCP servers for code review, research, design, and workflow automation.",
+  "version": "2.8.0",
+  "description": "AI-powered development tools. 24 agents, 16 commands, 11 skills, 2 MCP servers for code review, research, design, and workflow automation.",
   "author": {
     "name": "Kieran Klaassen",
     "email": "kieran@every.to",