[Improve] Clarify custom automation schedule metadata

[roomote-roomote]

Created by Roomote. Follow up by mentioning @roomote-roomote, in the web UI, or in Slack.

What changed

• Show human-readable summaries for custom cron schedules in the custom automation list.
• Present cadence, environment, branded destination, and channel as the primary metadata line.
• Move creator and optional relative last-run details to a secondary metadata line.
• Cover preset and custom schedules, destination labels, creator-only rows, and last-run rows in the render tests.

Why this change was made

Raw cron syntax and compressed metadata made custom automations harder to scan. The revised hierarchy makes the schedule and delivery target clear while retaining lightweight audit context.

Impact

Custom automation rows are easier to read across narrow and wide layouts, and custom schedules no longer expose crontab syntax in the list.

[roomote-community]

No code issues found. See task

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