Hive CLI output should support JSON format

To make it easier to extract critical fields from Hive CLI output, we should support a new argument `--output=json|text`.

This can be implemented on a per-command need but should be eventually supported on all commands. The most critical command is `schema:check`. The check ID and slug should be output as separate fields in the JSON output.

This will allow teams to use the schema check ID to call the public API and perform followup operations.

Start by locating the Hive CLI entry point and the schema:check command, then inspect how its current output exposes the check ID and slug. Define the --output=json|text behavior for that command first, and verify that JSON presents the ID and slug as separate fields while preserving text output.

Written by the indexing model from the issue text.