Summary: Modern mobile phones support larger image dimensions. Limit the image transform limits to show less distracting "It's a mystery" placeholder thumbnails to users. Closes T16414 Test Plan: * Create a PNG file with dimensions 8160px × 6144px * Upload via http://phorge.localhost/file/ * On resulting http://phorge.localhost/F3519, select "View Transforms" * Click "Regenerate" and/or embed the file via `{F3519}` in a Maniphest task comment * Get a placeholder image before, get a thumbnail after this patch Reviewers: O1 Blessed Committers, valerio.bozzolan Reviewed By: O1 Blessed Committers, valerio.bozzolan Subscribers: avivey, haylin, revi, tobiaswiese, valerio.bozzolan, Matthew, Cigaryno Maniphest Tasks: T16414 Differential Revision: https://we.phorge.it/D26661