feat(mobile): Remote thumbnails and images use an on-disk image cache (#7929)

* Fixes remote full / thumbnail provider

* Adds image cache manager to both remote image providers

format

format

Fix typo in equals

remove unused import

renames image loader

* Adds height and width to the image cache for thumbs

format

* Uses a separate remote and thumbnail cache

format

* Fixes key name

* Changes uri to string, fixes comment

* Chunk events are optional and remote thumbnails don't report chunk events

* better exception handling

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Co-authored-by: Alex Tran <alex.tran1502@gmail.com>

mobile/lib/modules/asset_viewer/image_providers/exceptions/image_loading_exception.dart

@@ -0,0 +1,5 @@
+/// An exception for the [ImageLoader] and the Immich image providers
+class ImageLoadingException implements Exception {
+  final String message;
+  ImageLoadingException(this.message);
+}