chore: enable MemPalace for project and ignore per-project files

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitignore

@@ -62,3 +62,7 @@ graphify-out/
 apps/pwa/test-results/
 apps/pwa/playwright-report/
 apps/pwa/blob-report/
+
+# MemPalace per-project files (issue #185)
+mempalace.yaml
+entities.json

.planning/config.json

@@ -92,5 +92,9 @@
   "graphify": {
     "enabled": true,
     "auto_update": true
+  },
+  "mempalace": {
+    "enabled": true,
+    "wing": "familysync"
   }
 }