Feature Request: Fixed/sticky input box at bottom (like Codex CLI)

Feature Request

Description
Add an option to pin/fix the input box at the bottom of the terminal, similar to OpenAI's Codex CLI. Currently, the input follows the content flow, which can be disorienting when there's a lot of output.

Desired Behavior

• Input box stays fixed at the bottom of the terminal
• Output/responses scroll above the input area
• Similar to a split-pane layout where the input is always visible and accessible

Why

• Better UX when working with long outputs — the input is always in a predictable position
• Codex CLI already implements this pattern and users find it intuitive
• Reduces cognitive load when switching between reading output and typing new prompts

Suggested Implementation

• Could be a setting like "inputPosition": "fixed-bottom" in settings.json
• Or a CLI flag like --sticky-input

Thank you!