Add error state to MangaCover composable (#7022)

* Add error state to MangaCover

- Add error drawable when thumbnailUrl isn't able to be loaded
- Tweak usage of MangaCover

* Change `contentDescription` to be nullable

As the invoke function makes default nulls

app/src/main/java/eu/kanade/presentation/util/Resources.kt

@@ -1,8 +1,14 @@
 package eu.kanade.presentation.util
 
+import android.content.res.Resources
+import androidx.annotation.DrawableRes
 import androidx.annotation.PluralsRes
 import androidx.compose.runtime.Composable
+import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.graphics.painter.BitmapPainter
 import androidx.compose.ui.platform.LocalContext
+import androidx.core.content.ContextCompat
+import androidx.core.graphics.drawable.toBitmap
 
 /**
  * Load a quantity string resource.
@@ -30,3 +36,19 @@ fun quantityStringResource(@PluralsRes id: Int, quantity: Int, vararg formatArgs
     val context = LocalContext.current
     return context.resources.getQuantityString(id, quantity, *formatArgs)
 }
+
+/**
+ * Create a BitmapPainter from an drawable resource.
+ *
+ * > Only use this if [androidx.compose.ui.res.painterResource] doesn't work.
+ *
+ * @param id the resource identifier
+ * @return the bitmap associated with the resource
+ */
+@Composable
+fun bitmapPainterResource(@DrawableRes id: Int): BitmapPainter {
+    val context = LocalContext.current
+    val drawable = ContextCompat.getDrawable(context, id)
+        ?: throw Resources.NotFoundException()
+    return BitmapPainter(drawable.toBitmap().asImageBitmap())
+}