Implement Stylus Prediction Metrics

Fills out the implementation and tests for MotionPredictorMetricsManager.

(Cherry pick of ag/23861881 from udc-qpr-dev)

Test: atest frameworks/native/libs/input/tests/MotionPredictorMetricsManager_test.cpp
Test: Manual testing on-device, computed metric values seem reasonable.

Bug: 268245099
Change-Id: Iec18415de9c3070f2b285c5c82f5a5e0ceaaf471