chore: remove image generation, Open WebUI, Lazytainer and neo4j

Drops the comfyui, downloader-comfyui, open-webui, lazytainer and neo4j
services with their volumes, env keys and update.sh steps, plus
scripts/switch-model.sh and the two image-generation research docs.

Refs #55 (removal inventory #58, intent vs. source #63)

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

scripts/update.sh

@@ -183,7 +183,6 @@ set_if_blank OMNIROUTE_STORAGE_ENCRYPTION_KEY "$(openssl rand -hex 32)"
 set_if_blank OMNIROUTE_MACHINE_ID_SALT "$(openssl rand -hex 16)"
 set_if_blank OMNIROUTE_CLI_SALT "$(openssl rand -hex 16)"
 set_if_blank OMNIROUTE_WS_BRIDGE_SECRET "$(openssl rand -hex 32)"
-set_if_blank NEO4J_PASSWORD "$(openssl rand -hex 16)"
 
 echo "==> resolving SEARXNG_LAN_IP"
 # search.home is a LAN mDNS/local-DNS name — resolvable from this host, just
@@ -227,7 +226,6 @@ docker compose build --pull
 echo "==> ensuring models are downloaded (skips already-present files)"
 docker compose --profile tools run --rm downloader
 docker compose --profile tools run --rm downloader-classifier
-docker compose --profile tools run --rm downloader-comfyui
 
 echo "==> bringing up omniroute"
 docker compose up -d --wait omniroute