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[kongo09]

Summary

• Implement the core scan/diff engine that reads learnt commands from Broadlink/tuya-local storage, diffs against known state, and dynamically creates or removes button entities
• Fix config flow to use SelectSelector (replaces vol.Coerce(list) which broke frontend serialization) and modernize OptionsFlow to use the base class config_entry property
• Add brand/ folder with mdi:remote icon for HA 2026.3+ local brand image support
• Add 7 tests for scan logic and service listener, plus a button press test

Key changes

• __init__.py: async_scan_remote_commands() resolves entity→device→storage key via registries, reads commands per remote, set-diffs to create/remove buttons. _make_service_listener() schedules delayed re-scans on learn_command/delete_command events
• button.py: Added async_setup_entry to store async_add_entities callback for dynamic entity creation
• config_flow.py: SelectSelector with multiple=True for remote entity selection; removed OptionsFlow.__init__ (uses inherited config_entry property)
• brand/: icon.png (256px) and icon@2x.png (512px), transparent background

Test plan

• Verify scan creates buttons when storage has new commands
• Verify scan removes entities when commands disappear from storage
• Verify service listener only triggers for watched remotes
• Verify config flow and options flow render correctly in HA frontend
• Verify brand icon displays on integrations page (requires HA 2026.3+)