Add MangaDex only implementation of Mangadex Follows list

Add login dialog that pops up whenever you are not logged in when trying to browse MangaDex
Remove attempts at porting over chapter read history from older galleries to new ones
Disable latest for ExHentai, it was browse without buttons anyway

app/src/main/java/exh/ui/metadata/MetadataViewController.kt

@@ -10,11 +10,12 @@ import eu.kanade.tachiyomi.data.database.models.Manga
 import eu.kanade.tachiyomi.databinding.MetadataViewControllerBinding
 import eu.kanade.tachiyomi.source.Source
 import eu.kanade.tachiyomi.source.SourceManager
-import eu.kanade.tachiyomi.source.online.MetadataSource.Companion.getMetadataSource
+import eu.kanade.tachiyomi.source.online.MetadataSource
 import eu.kanade.tachiyomi.ui.base.controller.NucleusController
 import eu.kanade.tachiyomi.ui.manga.MangaController
 import exh.metadata.metadata.base.FlatMetadata
 import exh.metadata.metadata.base.RaisedSearchMetadata
+import exh.source.EnhancedHttpSource.Companion.getMainSource
 import uy.kohesive.injekt.Injekt
 import uy.kohesive.injekt.api.get
 
@@ -73,9 +74,9 @@ class MetadataViewController : NucleusController<MetadataViewControllerBinding,
     }
 
     fun onNextMetaInfo(flatMetadata: FlatMetadata) {
-        val thisSourceAsLewdSource = presenter.source.getMetadataSource()
-        if (thisSourceAsLewdSource != null) {
-            presenter.meta = flatMetadata.raise(thisSourceAsLewdSource.metaClass)
+        val mainSource = presenter.source.getMainSource()
+        if (mainSource is MetadataSource<*, *>) {
+            presenter.meta = flatMetadata.raise(mainSource.metaClass)
         }
     }