Change libvips to be enabled by default (#34741)

config/application.rb

@@ -95,7 +95,7 @@ module Mastodon
       require 'mastodon/redis_configuration'
       ::REDIS_CONFIGURATION = Mastodon::RedisConfiguration.new
 
-      config.x.use_vips = ENV['MASTODON_USE_LIBVIPS'] == 'true'
+      config.x.use_vips = ENV['MASTODON_USE_LIBVIPS'] != 'false'
 
       if config.x.use_vips
         require_relative '../lib/paperclip/vips_lazy_thumbnail'

config/initializers/deprecations.rb

@@ -16,3 +16,9 @@ if ENV['REDIS_NAMESPACE']
 
   abort message
 end
+
+if ENV['MASTODON_USE_LIBVIPS'] == 'false'
+  warn <<~MESSAGE
+    WARNING: Mastodon support for ImageMagick is deprecated and will be removed in future versions. Please consider using libvips instead.
+  MESSAGE
+end