chore: switch postgres to official postgres:15.18 image (#720)
* chore: switch postgres to official postgres:15.18 image
Replace the unmaintained third-party ankane/pgvector:v0.5.1 image with
the official postgres:15.18 image. No data migration needed — existing
pg_data volumes are compatible.
* docs: drop stale pgvector reference from docker setup
Postgres image moved to official postgres:15.18; the extension is no
longer bundled and is unused, so the docker docs should not advertise it.
* Match the redis service by binding to localhost only for inter-container access
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Co-authored-by: Juan Mrad <juansmrad@gmail.com>