feat: add self-hosted memory providers (OpenViking, Honcho, Holographic)

- Add OpenViking service (knowledge graph) using official GHCR image
- Add Honcho stack (user modeling): API + PostgreSQL pgvector + Redis
- Add Holographic config to Hermes (local SQLite, no server needed)
- Hermes: install httpx for OpenViking client
- Hermes: auto-generate config.yaml + honcho.json on first boot
- All data 100% local, zero cloud dependencies

ai/hermes/config.yaml

@@ -0,0 +1,9 @@
+memory:
+  memory_enabled: true
+  user_profile_enabled: true
+  providers:
+    - holographic
+    - honcho
+    - openviking
+  flush_min_turns: 6
+  nudge_interval: 10