Use the Docker API instead of shelling out to podman; fix schema-appl…

[aersam]

…y retry and dependency parsing

• container.py: replace subprocess calls to the podman CLI with the docker package's client (docker.from_env(), falling back to Podman's rootful/rootless socket). Works against a real Docker daemon or Podman transparently, and needs no CLI binary or CI setup step - ubuntu-latest's preinstalled Docker daemon just works.
• schema.py apply_schema(): loop the failed-file retry until a full pass makes no more progress, instead of a single extra pass in original order - a multi-level dependency chain (e.g. view -> view -> table) could still raise on an item whose dependency hadn't had its own retry yet.
• schema.py _get_sql_deps(): pass error_level=IGNORE to sqlglot.parse() so one statement it can't fully parse (e.g. a schema-qualified DROP TRIGGER ... ON schema.table) doesn't lose every other statement's dependency info in the same file: fall back further to a regex scan if sqlglot still raises. This only feeds ordering, not execution, so an approximation is an acceptable fallback.