Introduce double_circle and segments-based patterns on the Pico, refactor the Presets engine to expose a logical ring over all strips, and migrate presets/test code from the old point pattern to segments while switching to a top-level presets.json.
Made-with: Cursor
Wire the Pico to UART-driven preset selection, add pattern modules and presets data, remove old p2p/settings code, and update tests and LED driver.
Made-with: Cursor
