fix(pointing): emit scaled smooth scrolling values

[te9no]

What changed

apply_resolution_scaling() now emits the scaled wheel value instead of the unscaled accumulated value.

Bug fixed

When CONFIG_ZMK_POINTING_SMOOTH_SCROLLING is enabled, the input listener computes a scaled wheel value and stores the remaining fractional part in remainder. Before this change, the function calculated scaled but assigned evt->value = val, so the accumulated unscaled value was emitted. This made scaling ineffective and allowed leftover remainder to affect later wheel events.

Local testing

• git diff --check passed.
• app/run-test.sh tests/pointing/mouse-scroll passed in a clean upstream ZMK workspace initialized from this PR branch with Zephyr v4.1.0+zmk-fixes.
• app/run-test.sh tests/pointing passed in the same clean upstream ZMK workspace.
• Hardware reproduction was observed on a split pointing-device build where enabling smooth scrolling caused right-side trackball scroll output to continue/repeat unexpectedly. Removing smooth scrolling avoided the issue; this one-line fix addresses the underlying scaling bug.

Requested testing

Additional testing with real hosts that negotiate HID resolution multipliers would be helpful.