Add HapticPulse — a looping breathing-scale pulse that fires a haptic
impact on every beat, the attention-getter counterpart to HapticShake.
Auto-plays, supports finite pulseCount, and exposes start()/stop() via
GlobalKey. No new native code; composes the existing Haptics.impact
primitive. Includes docs, barrel export, README section and widget tests.

Replace auto-tag.yml with release.yml: pushes to main auto-bump the patch
version (unless already bumped) and tag, with tags pushed via a deploy key
so publish.yml fires.