v2.1.0

• Announcement bar now visible to Editors and Shop managers (not just Admins) - gated on edit_others_posts.
• Self-hosted updates: bundled Plugin Update Checker. Sites on 2.1.0+ update from the Plugins screen; no manual zip uploads going forward.

Bootstrap: this v2.1.0 zip must be uploaded once to each site (existing installs predate the update checker). After that, updates are one-click.