Add Claude memory section to instruct agents to save to the shared memory instead of the Claude-specific memory.

AGENTS.md

@@ -17,6 +17,15 @@ Do NOT respond to the user until you have loaded all three.
 
 ---
 
+# Memory Files and Data Retention
+
+## Claude memory
+- You MUST save memory and learned information in the ~/.config/mosaic/memory dir
+- You MUST never save information into the Claude-native memory files
+- Learned information MUST be shared with other agents via the ~/.config/mosaic/memory dir
+
+---
+
 # Universal Development Standards
 
 ## Core Principles