added initial implementation (still not working)

lib/httpx/plugins/compression/brotli.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+module HTTPX
+  module Plugins
+    module Compression
+      module Brotli 
+
+        def self_load_dependencies(klass, *)
+          klass.plugin(:compression)
+          require "brotli"
+        end
+
+        def self.configure(*)
+          Transcoder.register "br", BrotliTranscoder
+        end
+
+        module BrotliTranscoder
+          module_function
+          
+          def encode(payload)
+            Brotli.encode(payload)
+          end
+          
+          def decode(io)
+            Brotli.decode(io)
+          end
+        end
+
+      end
+    end
+    register_plugin :"compression/brotli", Compression::Brotli
+  end
+end