Feature request: filters on chat messages and bulk chat delete #924

CLI version: 0.14.0

Use case: Cleaning up project chat lines in bulk, for example test lines or every line from one chatbot in a time window. Today that means listing with chat messages -n N --json, filtering with jq, and calling chat delete <id> --force once per line.

What's missing

• chat messages only takes --limit. There's no filter by creator, date range or text, and no pagination cursor.
• chat delete takes a single ID or URL.

Proposal

1. Filters on chat messages: --creator <person id|name> (including chatbots/integrations), --since <time>, --until <time>, --contains <text>, plus --all or a page cursor to go past the default 25.
2. Bulk delete: chat delete accepts several IDs/URLs, or the same filters as above (chat delete --creator MyBot --since 2026-10-01 --contains "test"), with:
   • --dry-run listing the matches without deleting,
   • the confirmation prompt showing the count and a preview, and --force required in non-interactive/--json mode (matching the current single-delete behavior),
   • per-line results in --json output (deleted / failed with reason).

Thanks!