Add ability to block words in usernames (#35407)

app/views/admin/username_blocks/_form.html.haml

@@ -0,0 +1,16 @@
+.fields-group
+  = form.input :username,
+               wrapper: :with_block_label,
+               input_html: { autocomplete: 'new-password', pattern: '[a-zA-Z0-9_]+', maxlength: Account::USERNAME_LENGTH_LIMIT }
+
+.fields-group
+  = form.input :comparison,
+               as: :select,
+               wrapper: :with_block_label,
+               collection: %w(equals contains),
+               include_blank: false,
+               label_method: ->(type) { I18n.t(type, scope: 'admin.username_blocks.comparison') }
+
+.fields-group
+  = form.input :allow_with_approval,
+               wrapper: :with_label

app/views/admin/username_blocks/_username_block.html.haml

@@ -0,0 +1,12 @@
+.batch-table__row
+  %label.batch-table__row__select.batch-table__row__select--aligned.batch-checkbox
+    = f.check_box :username_block_ids, { multiple: true, include_hidden: false }, username_block.id
+    .sr-only= username_block.username
+  .batch-table__row__content.pending-account
+    .pending-account__header
+      = t(username_block.exact? ? 'admin.username_blocks.matches_exactly_html' : 'admin.username_blocks.contains_html', string: content_tag(:samp, link_to(username_block.username, edit_admin_username_block_path(username_block))))
+      %br/
+      - if username_block.allow_with_approval?
+        = t('admin.email_domain_blocks.allow_registrations_with_approval')
+      - else
+        = t('admin.username_blocks.block_registrations')

app/views/admin/username_blocks/edit.html.haml

@@ -0,0 +1,10 @@
+- content_for :page_title do
+  = t('admin.username_blocks.edit.title')
+
+= simple_form_for @username_block, url: admin_username_block_path(@username_block) do |form|
+  = render 'shared/error_messages', object: @username_block
+
+  = render form
+
+  .actions
+    = form.button :button, t('generic.save_changes'), type: :submit

app/views/admin/username_blocks/index.html.haml

@@ -0,0 +1,26 @@
+- content_for :page_title do
+  = t('admin.username_blocks.title')
+
+- content_for :heading_actions do
+  = link_to t('admin.username_blocks.add_new'), new_admin_username_block_path, class: 'button'
+
+= form_with model: @form, url: batch_admin_username_blocks_path do |f|
+  = hidden_field_tag :page, params[:page] || 1
+
+  .batch-table
+    .batch-table__toolbar
+      %label.batch-table__toolbar__select.batch-checkbox-all
+        = check_box_tag :batch_checkbox_all, nil, false
+      .batch-table__toolbar__actions
+        = f.button safe_join([material_symbol('close'), t('admin.username_blocks.delete')]),
+                   class: 'table-action-link',
+                   data: { confirm: t('admin.reports.are_you_sure') },
+                   name: :delete,
+                   type: :submit
+    .batch-table__body
+      - if @username_blocks.empty?
+        = nothing_here 'nothing-here--under-tabs'
+      - else
+        = render partial: 'username_block', collection: @username_blocks, locals: { f: f }
+
+= paginate @username_blocks

app/views/admin/username_blocks/new.html.haml

@@ -0,0 +1,10 @@
+- content_for :page_title do
+  = t('admin.username_blocks.new.title')
+
+= simple_form_for @username_block, url: admin_username_blocks_path do |form|
+  = render 'shared/error_messages', object: @username_block
+
+  = render form
+
+  .actions
+    = form.button :button, t('admin.username_blocks.new.create'), type: :submit