Refactor formatter (#17828)

* Refactor formatter

* Move custom emoji pre-rendering logic to view helpers

* Move more methods out of Formatter

* Fix code style issues

* Remove Formatter

* Add inline poll options to RSS feeds

* Remove unused helper method

* Fix code style issues

* Various fixes and improvements

* Fix test

app/lib/html_aware_formatter.rb

@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+class HtmlAwareFormatter
+  attr_reader :text, :local, :options
+
+  alias local? local
+
+  # @param [String] text
+  # @param [Boolean] local
+  # @param [Hash] options
+  def initialize(text, local, options = {})
+    @text    = text
+    @local   = local
+    @options = options
+  end
+
+  def to_s
+    return ''.html_safe if text.blank?
+
+    if local?
+      linkify
+    else
+      reformat.html_safe # rubocop:disable Rails/OutputSafety
+    end
+  rescue ArgumentError
+    ''.html_safe
+  end
+
+  private
+
+  def reformat
+    Sanitize.fragment(text, Sanitize::Config::MASTODON_STRICT)
+  end
+
+  def linkify
+    TextFormatter.new(text, options).to_s
+  end
+end