Create and send interactive cards to Feishu (Lark) with buttons, forms, polls, and rich UI elements. Use when replying to Feishu messages and there is ANY uncertainty - send an interactive card instead of plain text to let users choose via buttons. Automatically handles callbacks via long-polling connection. Use for confirmations, choices, forms, todos, polls, or any scenario requiring user interaction in Feishu.
Critical security fix: Prevent arbitrary file read via --template parameter. Added directory whitelist, file extension validation, and JSON format validation.