autodetect language using rack middleware

Gemfile

@@ -105,3 +105,4 @@ gem "rails-controller-testing", "~> 1.0", group: :test
 gem "pundit", "~> 2.3"
 
 gem "spdx", "~> 4.1"
+gem "rack-contrib", "~> 2.3"

Gemfile.lock

@@ -288,6 +288,8 @@ GEM
       activesupport (>= 3.0.0)
     racc (1.7.3)
     rack (2.2.8)
+    rack-contrib (2.3.0)
+      rack (~> 2.0)
     rack-mini-profiler (3.3.0)
       rack (>= 1.2.0)
     rack-test (2.1.0)
@@ -522,6 +524,7 @@ DEPENDENCIES
   public_suffix (~> 5.0)
   puma (~> 6.4)
   pundit (~> 2.3)
+  rack-contrib (~> 2.3)
   rack-mini-profiler (~> 3.1)
   rails (~> 7.0.8)
   rails-controller-testing (~> 1.0)

config/application.rb

@@ -18,6 +18,8 @@ require "rails"
 rescue LoadError
 end
 
+require "rack/contrib"
+
 # Require the gems listed in Gemfile, including any gems
 # you've limited to :test, :development, or :production.
 Bundler.require(*Rails.groups)
@@ -48,5 +50,6 @@ module Manyfold
         )
       end
     end
+    config.middleware.use Rack::Locale
   end
 end