[Feature Request] Make Rewind keybindings (Cmd+Left/Right) configurable via keybindings.json

Bug Description
Title: Allow rebinding or disabling Cmd+Left / Cmd+Right (Rewind) via keybindings.json

Body:

Description

Cmd+Left and Cmd+Right open the Rewind feature (step back/forward through conversation messages). This shortcut is
hardcoded and not present in ~/.claude/keybindings.json, so it cannot be rebound or disabled.

This likely affects most macOS users, because Cmd+Option+Left / Cmd+Option+Right is the standard macOS shortcut for
switching between windows/tabs across virtually all applications. When pressing Cmd+Option+Left/Cmd+Option+Right, Claude
Code captures the Cmd+Left/Cmd+Right portion of the keystroke and triggers Rewind unexpectedly. This makes the standard
macOS window-switching workflow unreliable while Claude Code is focused.

Expected behavior

The Rewind keybinding should be configurable via ~/.claude/keybindings.json, like all other shortcuts — allowing users
to rebind or disable it.

Environment Info

• Platform: darwin
• Terminal: goland
• Version: 2.1.81
• Feedback ID: 5ca7a860-3901-4f60-b10f-60a6ee7d6c3d

Errors

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