input-field: Fix crash when numlock is on and numlock_color is fallba…

…ck (#673)

When numlock is enabled but numlock_color is fallback, `targetGrad`
remains nullptr. This causes Hyprlock to crash in updateColors().

This commit aligns the condition check for assigning `targetGrad` with
later usages.

src/renderer/widgets/PasswordInputField.cpp

@@ -418,7 +418,7 @@ void CPasswordInputField::updateColors() {
     CHyprColor          innerTarget = colorConfig.inner;
     CHyprColor          fontTarget  = (displayFail) ? colorConfig.fail->m_vColors.front() : colorConfig.font;
 
-    if (checkWaiting || displayFail || g_pHyprlock->m_bCapsLock || NUMLOCK) {
+    if (checkWaiting || displayFail || g_pHyprlock->m_bCapsLock || (NUMLOCK && !colorConfig.num->m_bIsFallback)) {
         if (BORDERLESS && colorConfig.swapFont) {
             fontTarget = targetGrad->m_vColors.front();
         } else if (BORDERLESS && !colorConfig.swapFont) {