Allow disabling input placeholder text via settings

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

The placeholder text "ctrl esc to focus or unfocus Claude" appears permanently
in the input field. For users who already know the shortcut, this text is
distracting and cannot be hidden.

Proposed Solution

Add a settings.json option such as "inputPlaceholderEnabled": false
to allow users to disable the placeholder text in the input field.

Alternative Solutions

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_