Add Drush Support

Summary

Implement first-party Drush support in entity_labels as a separate Drupal.org issue from #3581212, because the current checked-out
branch is for multilingual CSV behavior only. The feature will add four explicit commands for exporting and importing entity and
field label CSV data, reusing the module’s existing exporter/importer services rather than duplicating CSV logic.

Key Changes

Drupal.org contribution workflow

• Work from web/modules/sandbox/entity_labels, not the site root.
• Create a new Drupal.org issue for Drush support with scope limited to CLI export/import.
• Base the new issue branch from upstream 1.0.x, not from the current 3581212-language-support branch.

• Keep the MR focused on Drush support, tests, and README updates only.

  Public interfaces / commands

• Add a new Drush commands class at src/Commands/EntityLabelsCommands.php.

• Add drush.services.yml with a drush.command service tag.
• Expose these commands:
  • entity-labels:entity-export [--entity-type=TYPE]
  • entity-labels:field-export [--entity-type=TYPE] [--bundle=BUNDLE]
  • entity-labels:entity-import
  • entity-labels:field-import

• Command behavior:

  • Export commands write CSV to stdout.
  • Import commands read the given file, pass its raw contents to the existing importer service, and print a concise result
    summary (updated, skipped, and any reported errors).
  • entity-export supports --entity-type only.
  • field-export supports both scope options because the current field exporter already supports entity type and bundle drill-
    down.
  • Invalid file paths or unreadable files fail fast with a Drush error.
  • Importer/exporter exceptions are surfaced as Drush command failures with readable messages.

  Implementation details

• Inject and reuse existing services:

  • entity_labels.entity.exporter
  • entity_labels.field.exporter
  • entity_labels.entity.importer
  • entity_labels.field.importer
• Keep CSV generation consistent with the web UI by calling existing export() methods and streaming rows through fputcsv().
• Keep import behavior consistent with the web UI by reading file contents and calling existing import(string $csv) methods.
• Do not change routes, forms, or browser export/import behavior.
• Update README usage docs to include the four Drush commands and remove the current Drush TODO section.

• Do not add new module dependencies or change composer.json unless implementation reveals a hard requirement.

  Test Plan

• Add kernel coverage for the Drush commands layer, focused on behavior rather than re-testing exporter/importer internals.

• Export tests:
  • entity-export prints the expected CSV header and rows.
  • entity-export --entity-type=node limits output correctly.
  • field-export prints the expected header and respects --entity-type / --bundle.
• Import tests:
  • entity-import updates config through the existing importer and reports counts.
  • field-import updates field labels/descriptions and reports counts.
  • Missing or unreadable import file returns a command error.
  • Importer parse failures propagate as command errors.

• Run targeted module tests after implementation, at minimum the new Drush tests plus a sanity pass of existing entity/field
  importer/exporter tests.

  Assumptions and Defaults

• New Drupal.org issue, new issue fork, new MR.

• Four explicit commands are preferred over a grouped export/import command.
• entity-labels:entity-export will not support --bundle.
• Export output is plain CSV to stdout; no file-writing option is planned for v1.
• Import commands are non-interactive and use a required file path argument.
• No API/schema/config changes are intended beyond adding Drush command support.