Use CSS instead of server requests for image format in pet styles form

Instead of offering a form to request a different format, we just
render both in the HTML, and use CSS to swap between the two. Love to
see the `:has` filter come through for us!

app/assets/stylesheets/pet_states/support-outfit-viewer.sass

@@ -1,5 +1,4 @@
 @import "../partials/clean/constants"
-@import "../partials/context_button"
 
 support-outfit-viewer
 	display: flex
@@ -39,8 +38,16 @@ support-outfit-viewer
 			input[type=radio]
 				margin: 0
 
-		[type=submit]
-			+context-button
+	.outfit-viewer-area
+		> [data-format=png]
+			display: none
+
+	&:has(input[value=png]:checked)
+		.outfit-viewer-area
+			> [data-format=svg]
+				display: none
+			> [data-format=png]
+				display: block
 
 	> table
 		flex: 0 0 auto

app/views/pet_states/_support_outfit_viewer.html.haml

@@ -1,24 +1,21 @@
 = content_tag "support-outfit-viewer", **html_options do
-	= turbo_frame_tag "support-outfit-viewer-preview" do
 	%div
-			-# Render an outfit viewer in a magnifier. Use SVG by default for clarity,
-			-# but also offer an option to switch to PNG if it looks wrong.
-			%magic-magnifier
-				= outfit_viewer outfit,
-					preferred_image_format: params[:preferred_image_format] == "png" ? :png : :svg
+		.outfit-viewer-area
+			%magic-magnifier{"data-format": "svg"}
+				= outfit_viewer outfit, preferred_image_format: :svg
+			%magic-magnifier{"data-format": "png"}
+				= outfit_viewer outfit, preferred_image_format: :png
 
 		= form_with method: :get, class: "outfit-viewer-controls" do |f|
 			%fieldset
 				%legend Format
 				%label
 					= f.radio_button "preferred_image_format", "svg",
-							checked: params[:preferred_image_format] != "png"
+					  checked: true
 					SVG
 				%label
-						= f.radio_button "preferred_image_format", "png",
-							checked: params[:preferred_image_format] == "png"
+					= f.radio_button "preferred_image_format", "png"
 					PNG
-				= f.submit "Update"
 
 	%table
 		%thead