Improve accessibility (part 3) (#4405)

* fix(compose): Add aria-label for the navigation links

* fix(search): Add input label

* fix(navigation_bar): Link description

* fix(autosuggest_textarea): Add input label

* fix(compose_form): Add input label

* fix(upload_button): Add input label

* fix(account/header): Add link content

* fix(column_header): Use h1 tag

* fix(column_header): Labels move buttons moving column

* fix(settings_text): Add label to input

* fix(column_header): Remove role from h1

* fix(modal_root): Use role=dialog

* fix(modal_root): Focus restauration

* fix(modal_root): Apply inert to sibligs

* fix(column_header): Add role=button

* chore(eslint): Disable jsx-a11y/label-has-for

app/javascript/mastodon/locales/ja.json

@@ -35,6 +35,8 @@
   "column.public": "連合タイムライン",
   "column_back_button.label": "戻る",
   "column_header.hide_settings": "設定を隠す",
+  "column_header.moveLeft_settings": "Move column to the left",
+  "column_header.moveRight_settings": "Move column to the right",
   "column_header.pin": "ピン留めする",
   "column_header.show_settings": "設定を表示",
   "column_header.unpin": "ピン留めを外す",