v0.1.10: Customizer follow-ups

What's changed

• Adds the auto-save customizer flow with Undo, Retry, Done, and Escape to close.
• Lets Escape cancel an active pointer drag before leaving customize mode.
• Adds returning drop target hints while reordering.
• Keeps row move menus quiet until hover or focus while preserving keyboard access.
• Stabilizes icon color and opacity across wp-admin color schemes and plugin icon types.

Notes for hosts

• No WPCOM integration adapter changes are required for this release.
• The release asset is the wp-admin-sidebar.zip package expected by the WPCOM vendoring script.