fix: correct zacdcook credit link formatting

Make markdown links consistent with other credits.

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

Author: Spacehunterz

README.md

@@ -351,7 +351,7 @@ SOFTWARE.
 ## Credits
 
 - **Agent Pool:** [wshobson/agents](https://github.com/wshobson/agents) - 100 specialized agent personas by [@wshobson](https://github.com/wshobson)
-- **Persistent semantic memory system for Claude Code** https://github.com/zacdcook/claude-code-semantic-memory by [@zacdcook]
+- **Persistent semantic memory system for Claude Code:** [zacdcook/claude-code-semantic-memory](https://github.com/zacdcook/claude-code-semantic-memory) by [@zacdcook](https://github.com/zacdcook)
 
 ## Contributors 🙏