feat: add qdrant and neo4j for RAG vector/graph storage

Adds the two databases as infra services (own volume, ai-stack
network, host-published UI ports like comfyui) for an upcoming RAG
pipeline. Extraction/chunking/orchestration code is out of scope for
this repo — it's app logic that calls into these DBs and llama-server,
not compose infra.

Neo4j password follows the omniroute secret pattern: blank in
.env.example, auto-generated by scripts/update.sh.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DjhxWirQepKFEQj1huXNJR

docker-compose.yml

@@ -303,6 +303,34 @@ services:
     depends_on:
       - llama-server
 
+  # RAG vector store — see docs/agents/... (wayfinder). Dashboard UI published
+  # directly like comfyui above, not gatewayed through omniroute (it isn't an
+  # LLM provider).
+  qdrant:
+    image: qdrant/qdrant:latest
+    container_name: qdrant
+    volumes:
+      - qdrant-data:/qdrant/storage
+    ports:
+      - "6333:6333"
+    restart: unless-stopped
+    networks: [ai-stack]
+
+  # RAG graph store, native vector index too (can absorb qdrant's job later
+  # if the two-DB split proves unnecessary — see wayfinder notes).
+  neo4j:
+    image: neo4j:5-community
+    container_name: neo4j
+    environment:
+      - NEO4J_AUTH=neo4j/${NEO4J_PASSWORD:?run scripts/update.sh first to resolve this}
+    volumes:
+      - neo4j-data:/data
+    ports:
+      - "7474:7474" # browser UI
+      - "7687:7687" # bolt
+    restart: unless-stopped
+    networks: [ai-stack]
+
 networks:
   ai-stack:
 
@@ -310,3 +338,5 @@ volumes:
   models:
   omniroute-data:
   comfyui-data:
+  qdrant-data:
+  neo4j-data: