Improve credit line in image list (#6295)

- When author is not uploader, show both.
- When failing to parse author from HTML, use structured data.

app/src/main/java/fr/free/nrw/commons/utils/MediaAttributionUtil.kt

@@ -0,0 +1,39 @@
+package fr.free.nrw.commons.utils
+
+import android.content.Context
+import android.icu.text.ListFormatter
+import android.os.Build
+import fr.free.nrw.commons.Media
+import fr.free.nrw.commons.R
+import fr.free.nrw.commons.media.IdAndLabels
+import java.util.Locale
+
+object MediaAttributionUtil {
+    fun getTagLine(media: Media, context: Context): String {
+        val uploader = media.user
+        val author = media.getAttributedAuthor()
+        return if (author.isNullOrEmpty()) {
+            context.getString(R.string.image_uploaded_by, uploader)
+        } else if (author == uploader) {
+            context.getString(R.string.image_tag_line_created_and_uploaded_by, author)
+        } else {
+            context.getString(
+                R.string.image_tag_line_created_by_and_uploaded_by,
+                author,
+                uploader
+            )
+        }
+    }
+
+    fun getCreatorName(idAndLabels: List<IdAndLabels>): String? {
+        val locale = Locale.getDefault()
+        val names = idAndLabels.map{ x -> x.getLocalizedLabel(locale.language)}
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+            val formatter = ListFormatter.getInstance(locale)
+            return formatter.format(names)
+        } else {
+            return names.joinToString(", ")
+        }
+    }
+
+}

app/src/main/java/fr/free/nrw/commons/utils/StringUtil.kt

@@ -1,9 +1,8 @@
 package fr.free.nrw.commons.utils
 
-import android.os.Build
-import android.text.Html
 import android.text.Spanned
 import android.text.SpannedString
+import androidx.core.text.HtmlCompat
 
 object StringUtil {
 
@@ -26,12 +25,6 @@ object StringUtil {
             .replace("‏", "\u200F")
             .replace("&", "&")
 
-        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
-            Html.fromHtml(processedSource, Html.FROM_HTML_MODE_LEGACY)
-        } else {
-            //noinspection deprecation
-            @Suppress("DEPRECATION")
-            Html.fromHtml(processedSource)
-        }
+        return HtmlCompat.fromHtml(processedSource, HtmlCompat.FROM_HTML_MODE_LEGACY)
     }
 }