add rails erd

Gemfile.lock

@@ -83,6 +83,7 @@ GEM
       msgpack (~> 1.0)
     builder (3.2.4)
     byebug (11.1.3)
+    choice (0.2.0)
     coderay (1.1.3)
     concurrent-ruby (1.1.9)
     crass (1.0.6)
@@ -207,6 +208,11 @@ GEM
     rails-dom-testing (2.0.3)
       activesupport (>= 4.2.0)
       nokogiri (>= 1.6)
+    rails-erd (1.6.1)
+      activerecord (>= 4.2)
+      activesupport (>= 4.2)
+      choice (~> 0.2.0)
+      ruby-graphviz (~> 1.2)
     rails-html-sanitizer (1.3.0)
       loofah (~> 2.3)
     railties (6.1.4)
@@ -264,6 +270,8 @@ GEM
       rubocop-ast (>= 1.1.0)
     rubocop-shopify (2.2.0)
       rubocop (~> 1.18)
+    ruby-graphviz (1.2.5)
+      rexml
     ruby-progressbar (1.11.0)
     ruby-vips (2.1.2)
       ffi (~> 1.12)
@@ -340,6 +348,7 @@ DEPENDENCIES
   puma (~> 5.0)
   pundit
   rails (~> 6.1.4)
+  rails-erd
   rspec-graphql_matchers (~> 1.3)
   rspec-rails
   rubocop-rails