feat(tap): add tap gesture recognition with multi-tap support

[devjaewon]

Summary

• Add new @cereb/tap package for tap gesture recognition
• Support multi-tap detection (single, double, triple taps, etc.)
• Add double-tap zoom gesture to space adventure example

Features

Operators

• tapRecognizer() - Full lifecycle operator emitting start, end, and cancel phases
• tapEndOnly() - Simplified operator that only emits successful tap events
• tap() - Convenience function that creates a tap stream from an element

Configuration Options

Option	Default	Description
movementThreshold	10px	Max movement allowed during tap
durationThreshold	500ms	Max duration for a valid tap
chainMovementThreshold	movementThreshold	Max distance between consecutive taps
chainIntervalThreshold	durationThreshold / 2	Max interval between consecutive taps

TapSignal Value

• phase: Tap lifecycle phase (start, end, cancel)
• x, y: Client coordinates
• pageX, pageY: Page coordinates
• tapCount: Consecutive tap count (1=single, 2=double, etc.)
• duration: How long the pointer was pressed (ms)
• pointerType: Type of pointer (mouse, touch, pen)

Usage Example

import { tap } from "@cereb/tap";

tap(element, { chainIntervalThreshold: 300 })
  .on((signal) => {
    if (signal.value.tapCount === 2) {
      console.log("Double tap detected!");
    }
  });