Feature Request: Shift+Enter for newlines in message input

Feature Request

Current Behavior:
Pressing Shift+Enter immediately submits the partially typed message, the same as pressing Enter alone.

Desired Behavior:
Shift+Enter should insert a newline/blank line in the message, allowing users to compose multi-line messages before submitting with Enter.

Rationale:

• This matches the standard behavior of most chat interfaces (Slack, Discord, Teams, VS Code chat, etc.)
• Multi-line messages are useful for:
• Providing structured input with clear separation
• Pasting code snippets with context
• Writing prompts that benefit from paragraph breaks
• Better readability for complex requests

Current Workarounds:

• Typing in an external editor and pasting
• Using piped input from files

These workarounds are functional but interrupt the interactive flow of the CLI.

Suggested Implementation:

• Shift+Enter: Insert newline
• Enter: Submit message
• (Optional) Ctrl+Enter as alternative submit for consistency with some editors

Thank you for considering this enhancement!