* Add lettabot-history CLI
* Document and test lettabot-history
* Validate lettabot-history limit
* fix: address review feedback on history CLI
- Extract shared loadLastTarget into cli/shared.ts (was duplicated in message.ts, react.ts, history-core.ts)
- Clamp --limit to platform maximums (Discord: 100, Slack: 1000)
- Fix Discord author formatting: use globalName/username instead of deprecated discriminator
- Add Slack fetch test
Written by Cameron ◯ Letta Code
"You miss 100% of the shots you don't take." -- Wayne Gretzky -- Michael Scott
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Co-authored-by: Jason Carreira <jason@visotrust.com>
Co-authored-by: Cameron <cameron@pfiffer.org>
