[#493][CRUD] Add the form view templates to the generator (#506)

* [#483] Add tests to the CRUD layout

* [#483] Fix the check for slim and erb layout files

* [#493] Add slim view templates for new, form, and edit

* [#493] Fix view error

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Co-authored-by: Xavier MALPARTY <xavier@nimblehq.co>

.template/addons/crud/lib/templates/slim/scaffold/_form.html.slim.tt

@@ -0,0 +1,28 @@
+= form_with(model: <%= model_resource_name %>) do |form|
+  - if <%= singular_table_name %>.errors.any?
+    div style="color: red"
+      h2 = "#{pluralize(<%= singular_table_name %>.errors.count, "error")} prohibited this <%= singular_table_name %> from being saved:"
+      ul
+        - <%= singular_table_name %>.errors.each do |error|
+          li = error.full_message
+
+<% attributes.each do |attribute| -%>
+  .mb-3
+<% if attribute.password_digest? -%>
+    = form.label :password, class: 'form-label'
+    = form.password_field :password, class: 'form-control'
+
+  .mb-3
+    = form.label :password_confirmation, class: 'form-label'
+    = form.password_field :password_confirmation, class: 'form-control'
+<% elsif attribute.attachments? -%>
+    = form.label :<%= attribute.column_name %>, class: 'form-label'
+    = form.<%= attribute.field_type %> :<%= attribute.column_name %>, multiple: true, class: 'form-control'
+<% else -%>
+    = form.label :<%= attribute.column_name %>, class: 'form-label'
+    = form.<%= attribute.field_type %> :<%= attribute.column_name %>, class: 'form-control'
+<% end -%>
+
+<% end -%>
+  div
+    = form.submit 'Submit', class: 'btn btn-primary'

.template/addons/crud/lib/templates/slim/scaffold/edit.html.slim.tt

@@ -0,0 +1,8 @@
+h1 Editing <%= human_name.downcase %>
+
+== render "form", <%= singular_table_name %>: @<%= singular_table_name %>
+
+br
+
+div
+  =< link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper(type: :path) %>, class: 'btn btn-secondary'

.template/addons/crud/lib/templates/slim/scaffold/new.html.slim.tt

@@ -0,0 +1,10 @@
+content_for :title, "New <%= human_name.downcase %>"
+
+h1 New <%= human_name.downcase %>
+
+== render 'form', <%= singular_table_name %>: @<%= singular_table_name %>
+
+br
+
+div
+  = link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper(type: :path) %>