build(docker): harden apt against transient Ubuntu-mirror failures
Drops an /etc/apt/apt.conf.d/99-retries file into every ubuntu:24.04 stage before the first apt call: Acquire::Retries "5"; Acquire::http::Timeout "30"; Acquire::https::Timeout "30"; Acquire::http::No-Cache "true"; Motivation: docker compose builds on shared hosts have been hitting "File has unexpected size" errors from security.ubuntu.com when a mirror edge is mid-sync. Retries + No-Cache let apt transparently re-fetch from a fresh mirror instance instead of failing the whole build. Does not help when the mirror is serving a permanently-wrong file (nothing does), but cleans up the common transient case. Applied to: - api/Dockerfile (build-common) - yaci-indexer/Dockerfile (build-common) - docker/dockerfiles/mithril/Dockerfile (cardano-builder + mithril-runner) - docker/dockerfiles/node/Dockerfile (cardano-builder + node-runner) - docker/dockerfiles/postgres/Dockerfile Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>