Implements the `agent send` command for sending messages to existing agents.
Features:
- Send follow-up tasks to running agents
- Support for ID prefix matching (e.g., "a1b2" matches "a1b2c3d4")
- --no-wait flag to return immediately without waiting for completion
- Default behavior waits for agent to become idle
Usage:
paseo agent send <id> <prompt>
paseo agent send --no-wait a1b2c3d "Run the linter"
Mohamed Boudra
851d5ef247