[BOOK-351] fix: 온보딩 그래픽 이미지 양쪽에 패딩이 존재하는 문제 해결

ContentScale 지정 및 fillMaxWidth을 통해 양쪽을 꽉 채우도록 조정

Author: easyhooon

feature/onboarding/src/main/kotlin/com/ninecraft/booket/feature/onboarding/component/OnboardingPage.kt

@@ -4,11 +4,13 @@ import androidx.compose.foundation.Image
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
@@ -25,16 +27,20 @@ internal fun OnboardingPage(
     titleRes: Int,
     highlightTextRes: Int,
     descriptionRes: Int,
+    modifier: Modifier = Modifier,
 ) {
     Column(
-        modifier = Modifier.fillMaxSize(),
+        modifier = modifier.fillMaxSize(),
         horizontalAlignment = Alignment.CenterHorizontally,
     ) {
         Spacer(modifier = Modifier.weight(1f))
         Image(
             painter = painterResource(imageRes),
             contentDescription = "Onboarding Graphic",
-            modifier = Modifier.height(274.dp),
+            contentScale = ContentScale.FillWidth,
+            modifier = Modifier
+                .fillMaxWidth()
+                .height(274.dp),
         )
         Spacer(modifier = Modifier.height(ReedTheme.spacing.spacing8))
         Text(