Rename database services to db and cache services to cache, with their
volumes as db-data and cache-data, in litellm, owncloud and goclaw. Rename
the couchbase and open-webui volumes to <service>-data. Data on miti-sg was
copied into the new volumes beforehand; the old volumes are kept.
alloy: move to latest tags (no moving major tag upstream), trim comments to what each line does.
diun: order .env.example like compose.yml.
couchbase: add .env.example, drop the version key, explain the published ports.
tiennm99