fix: attachment file handling - real files, inline preview, click to open

- FileService: use Storage::temporaryUrl() standard API instead of manual signed route
- FileService: added isImage() and getPreviewUrl() helpers
- Seeder: create actual files on disk instead of fake paths
- Edit Feedback: new 'Attachments' section showing all feedback files with thumbnails
- Interactions modal: image preview thumbnails + inline click-to-open
- New footer layout: edit-footer.blade.php wrapper for attachments + similar cases

app/Filament/Resources/Feedback/RelationManagers/InteractionsRelationManager.php

@@ -143,6 +143,7 @@ class InteractionsRelationManager extends RelationManager
                                 'url' => $fileService->getTemporaryUrl($a, 60),
                                 'size' => $a->size ? round($a->size / 1024, 1) . ' KB' : 'N/A',
                                 'collection' => $a->collection,
+                                'mime_type' => $a->mime_type,
                             ];
                         });