fix: collapse the triple auto-switch re-apply in the Options OK handler

[bnayahu]

Closes #2

Problem

OptionsDialogProc's IDOK handler could call CheckAndApplyAutoSwitch() three times per click — in the auto-switch settings block, in the base-mouse-count block, and in the forced re-apply after the cached device state is discarded. Each call enumerates raw input devices with up to three GetRawInputDeviceList retries.

Why it was safe, and why it is still safe

• The direction is persisted before all three calls, so none could read a stale value.
• ApplyMouseOrientation() passes an absolute value to SwapMouseButton() rather than toggling, so repeated application is idempotent.
• In the common case the first two calls early-return on unchanged state, so only the last one did work.

Change

Remove the two earlier calls; keep the forced re-apply at the end of the handler, still gated on autoSwitchEnabled && autoSwitchWritten and still preceded by the g_lastExternalMouseState = EXTERNAL_MOUSE_UNKNOWN reset that makes it effective.

The surviving call is strictly the better one: by the end of the handler every setting it reads — direction, auto-switch flag, base device count — is persisted. The first call ran before SetBaseMouseCount(), so it could never see a changed base count.

Dropping the base-mouse-count call also closes a small inconsistency: it was gated on autoSwitchEnabled alone, so it could re-apply even when the auto-switch flag failed to persist and monitoring was never started. The surviving call is gated on both, matching 3a00a42.

Verification

• ./build.sh succeeds, no compiler warnings.
• Net effect per OK click: one device enumeration instead of up to three; no change to the resulting mouse orientation in any path.

Assisted-By: Claude (Anthropic AI) noreply@anthropic.com