Fix/source mangas white screen when directly open page via url (#362)

* Correctly handle missing location state

In case the view gets opened directly via url, there won't be any location state.
This leads to a TypeError when trying to get "contentType" from the location state.
Issue was introduced with 4e8813b526 where the function was adapted incorrectly with code that will never work (good job me KEKW)

* Add info about dev mode + strict mode issue

src/screens/SearchAll.tsx

@@ -123,6 +123,9 @@ const SourceSearchPreview = React.memo(
 
         useEffect(
             () => () => {
+                // INFO:
+                // with strict mode + dev mode the first request will be aborted. due to using SWR there won't be an
+                // immediate second request since it's the same key. instead the "second" request will be the error handling of SWR
                 abortRequest(
                     new Error(`SourceSearchPreview(${source.id}, ${source.displayName}): search string changed`),
                 );

src/screens/SourceMangas.tsx

@@ -163,9 +163,10 @@ export default function SourceMangas() {
     const { sourceId } = useParams<{ sourceId: string }>();
 
     const navigate = useNavigate();
-    const { state: { contentType: currentLocationContentType = SourceContentType.POPULAR } = {} } = useLocation<{
-        contentType: SourceContentType;
-    }>();
+    const { contentType: currentLocationContentType = SourceContentType.POPULAR } =
+        useLocation<{
+            contentType: SourceContentType;
+        }>().state ?? {};
 
     const { options } = useLibraryOptionsContext();
     const [query] = useQueryParam('query', StringParam);
@@ -247,6 +248,9 @@ export default function SourceMangas() {
                 return;
             }
 
+            // INFO:
+            // with strict mode + dev mode the first request will be aborted. due to using SWR there won't be an
+            // immediate second request since it's the same key. instead the "second" request will be the error handling of SWR
             abortRequest(new Error(`SourceMangas(${sourceId}): search string changed`));
         },
         [searchTerm, contentType],