feat: add entities to /purge command

[DereC4]

tried to keep as many things in place as possible, and used the entity ID utility functions from the class to map entity to their numeric ID

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[agusmeroli]

This would be a very welcome addition, however this PR doesn't actually do what it says. I have tested this, turns out that's not how the database schema is set up unfortunately, it just throws SQLITE errors if an entity id is provided.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[Intelli]

Entity-type filtering for purge would be a useful addition, but this implementation needs changes before merging.

• Entity kills are stored in co_block (action=3, type=entity ID); co_entity contains linked metadata and has no type column. Please filter the actual entity event rows, distinguish entity actions from material actions, and handle linked metadata safely.
• There are also regressions: unfiltered global SQLite purges retain all block/entity rows; block-filtered global SQLite purges remove unrelated history; entity-only MySQL purges ignore the entity restriction; and world-scoped SQLite entity purges remove unrelated block history.
• Please rebase onto the current purge implementation and apply entity filtering consistently across supported backends, preserving existing unfiltered, block-filtered, world and time-range behavior.