RumiCar-lib v0.5.0 released

We have released RumiCar-lib v0.5.0. The release notes below are also available on GitHub.

What’s new

Exercise-4 — improving a sketch together with an AI coding agent (new chapter of the RumiCar hands-on textbook 3.0). Four new example sketches:
- Exercise-4.1 — starting point for “forward and reverse without slipping”: the same code as Exercise-2.3, plus AGENTS.md.
- Exercise-4.1-Answer — one answer: ramp the PWM up and down and brake before changing direction.
- Exercise-4.2 — starting point for “a car that backs out when it gets stuck”: the same code as Exercise-3.2, plus AGENTS.md.
- Exercise-4.2-Answer — one answer: three ways to detect that the car is stuck (direction flips / no progress / three sides close) and a bounded back-and-turn escape.
AGENTS.md inside Exercise-4.1 and Exercise-4.2: the rules an AI agent (the textbook uses Google’s Antigravity CLI, agy) must follow — edit only the .ino, use only the RumiCar API, bounded reversing, compile-check with the IDE’s bundled arduino-cli, never upload, reply in the user’s language. Arduino IDE shows it as a tab next to the sketch and copies it along with File > Save As. Japanese rules with an English summary at the top.
README: Exercise-4 section; board settings by CM connector (Type-C → “ATmega328P”, older Mini-USB / Micro-USB → “ATmega328P (Old Bootloader)”); versioning note.
CI: new compile-examples workflow builds every example for arduino:avr:nano:cpu=atmega328 and cpu=atmega328old; lint checks that both AGENTS.md copies are identical.

Library source (src/) and public API are unchanged. Exercise-1.1 … 3.2 and Basic are unchanged.

The detection thresholds in Exercise-4.2-Answer are starting points; tuning from real courses will ship as v0.5.1, v0.5.2, … Please report results as Issues.