Add expand/compress image button on image view box (#15068)

* add zoom image button

* enhance zoom algorithm & add translation

* code structure

* code structure

* code structure

* enhance grab performance

* rm useless state

* fix behavior on Firefox & scroll lock & horizontal scroll with mousewheel

* remove scroll lock on MouseWheelEvent

* code structure

* enhance algorithm and code structure

* rm Gemfile.lock from tree

* codeclimate

* fix a stupid mistake

app/javascript/mastodon/locales/en.json

@@ -254,6 +254,8 @@
   "keyboard_shortcuts.unfocus": "to un-focus compose textarea/search",
   "keyboard_shortcuts.up": "to move up in the list",
   "lightbox.close": "Close",
+  "lightbox.compress": "Compress image view box",
+  "lightbox.expand": "Expand image view box",
   "lightbox.next": "Next",
   "lightbox.previous": "Previous",
   "lightbox.view_context": "View context",