[FEATURE] Support mouse click to reposition cursor in input box

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When editing longer prompts or pasting text into the Claude Code input box, repositioning the cursor requires repeated use of arrow keys or keyboard shortcuts (Alt+F/B, Home/End). In every other text input I use (editors, browsers, IDEs), I can click to place my cursor exactly where I want. The lack of mouse support makes editing multi-line or complex prompts slow and frustrating.

Proposed Solution

Clicking within the input box should move the text cursor to the clicked position, the same way it works in any standard text field. If the click lands beyond the end of the text, the cursor should move to the end. No extra modifier keys needed - just a plain left click.

Alternative Solutions

_No response_

Priority

Low - Nice to have

Feature Category

CLI commands and flags

Use Case Example

1. I paste a multi-line code snippet into the input box
2. I notice a typo near the beginning of the second line
3. Currently: I have to press Up, then Home, then arrow/Alt+F multiple times to reach the typo
4. With this feature: I click on the typo, fix it, and keep going

Additional Context

_No response_