Use file mime type for picture by format select

Active storage has the mime type stored not the extension.

app/models/alchemy/picture.rb

@@ -91,7 +91,9 @@ def self.preprocessor_class=(klass)
     scope :recent, -> { where("#{table_name}.created_at > ?", Time.current - 24.hours).order(:created_at) }
     scope :deletable, -> { where("#{table_name}.id NOT IN (SELECT picture_id FROM #{EssencePicture.table_name})") }
     scope :without_tag, -> { left_outer_joins(:taggings).where(gutentag_taggings: { id: nil }) }
-    scope :by_file_format, ->(format) { where(image_file_format: format) }
+    scope :by_file_format, ->(file_format) {
+        with_attached_image_file.joins(:image_file_blob).where(active_storage_blobs: { content_type: file_format })
+      }
 
     # Class methods
 
@@ -111,14 +113,10 @@ def url_class=(klass)
       end
 
       def alchemy_resource_filters
-        file_types = file_formats.map do |format|
-          MiniMime.lookup_by_content_type(format)&.extension
-        end
-
         [
           {
             name: :by_file_format,
-            values: file_types,
+            values: file_formats,
           },
           {
             name: :misc,

config/locales/alchemy.en.yml

@@ -118,6 +118,7 @@ en:
         by_file_format:
           name: File Type
           values:
+            <<: *mime_types
             gif: GIF Image
             jpeg: JPG Image
             png: PNG Image