feat(main): add option to sync current editable buffer with parent buffer - #192

This pull request introduces a new feature that keeps the parent window's buffer in sync with the zen window in Zen Mode, which is particularly useful for preserving buffer state (such as LSP) when switching buffers. The implementation includes a new configuration option, supporting logic, and event-driven synchronization.

Feature: Parent Buffer Synchronization

• Added a sync_parent_buffer configuration option (enabled by default) to the Zen Mode setup, allowing users to keep the parent window's buffer synchronized with the zen window.
• Introduced the sync_parent_buffer_enabled flag and related logic in view.lua to control whether buffer synchronization is active.
• Added an autocommand on BufEnter to trigger buffer synchronization between the zen window and its parent window.
• Implemented the sync_parent_buffer function in view.lua to perform the actual buffer synchronization when appropriate.
• Exposed a new sync_parent_buffer function in plugins.lua to allow toggling the synchronization feature programmatically.