chore(hanzo-memory): drop orphaned Redis service from compose (#34)

The `memory` service never set REDIS_URL and never wired itself to the
Redis container. Runtime config (src/hanzo_memory/config.py) defaults
redis_url=None — caching via Redis is optional and unconfigured. The
`redis:` block was a dead, profile-gated (with-cache) declaration with
no consumer.

Per "no redis, no kv" policy: remove the orphaned block and its volume.
No consumer migration needed (nothing consumed it).

pkg/hanzo-memory/compose.yml

@@ -18,17 +18,4 @@ services:
       test: ["CMD", "curl", "-f", "http://localhost:4000/health"]
       interval: 30s
       timeout: 10s
-      retries: 3
-
-  # Optional: Redis for caching
-  redis:
-    image: redis:7-alpine
-    ports:
-      - "6379:6379"
-    volumes:
-      - redis_data:/data
-    profiles:
-      - with-cache
-
-volumes:
-  redis_data:
+      retries: 3