fix(mem0-agent): emit the Claude Code manifest at hooks/hooks.json

Claude Code auto-discovers a plugin's hooks at <plugin>/hooks/hooks.json. The
generator was writing to hooks/generated/, so the manifest existed but was never
loaded and no hook would have fired on install.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

integrations/mem0-agent/hooks/hooks.spec.yaml

@@ -29,7 +29,7 @@ defaults:
 editors:
   - id: claude-code
     supported: true
-    output: "generated/claude-code.hooks.json"
+    output: "hooks.json"   # Claude Code auto-discovers <plugin>/hooks/hooks.json
     dialect: "claude-code"
     env:
       MEM0_EDITOR: "claude-code"