The DevKitC-1 has no discrete LED on GPIO 2, so the Spike 1 blink was
invisible without external wiring. Drive the on-board addressable LED
(WS2812 on GPIO 48) each cycle for visible confirmation on the bench.
Generated from esp-rs/esp-idf-template for the ESP32-S3 std target.
src/main.rs toggles GPIO 2 every 500 ms and logs `blink N` over USB-
serial — the minimum bring-up surface called out in
docs/v0.1-mvp-technical.md (Spike 1: confirm toolchain, flash, and basic
GPIO). edition=2024 with rust-version=1.85.
No editor/render/git/usb/fs modules yet; those land per the spike
methodology when later spikes need them.