web: move all strings to i18n & improve a11y

- omnibox is now fully usable with a screen reader
- back button is now interpreted as such
- subtext now accepts line breaks

web/src/routes/settings/save/metadata/+page.svelte

@@ -1,40 +1,42 @@
 <script lang="ts">
+    import { t } from "$lib/i18n/translations";
+
+    import { filenameStyleOptions } from "$lib/types/settings";
+
     import SettingsCategory from "$components/settings/SettingsCategory.svelte";
     import Switcher from "$components/buttons/Switcher.svelte";
     import SettingsButton from "$components/buttons/SettingsButton.svelte";
     import SettingsToggle from "$components/buttons/SettingsToggle.svelte";
-
-    import { filenameStyleOptions } from "$lib/types/settings";
 </script>
 
 <SettingsCategory
-    title="filename style"
-    description="very cool description for every style. bla bla bla."
+    title={$t("settings.metadata.filename")}
+    description={$t("settings.metadata.filename.description")}
 >
     <Switcher big={true}>
         {#each filenameStyleOptions as value}
             <SettingsButton settingContext="save" settingId="filenameStyle" settingValue={value}>
-                {value}
+                {$t(`settings.metadata.filename.${value}`)}
             </SettingsButton>
         {/each}
     </Switcher>
 
 </SettingsCategory>
 
-<SettingsCategory title="file metadata">
+<SettingsCategory title={$t("settings.metadata.file")}>
     <SettingsToggle
         settingContext="save"
         settingId="disableMetadata"
-        title="disable file metadata"
-        description="cobalt won't add title, artist, and other info to the file."
+        title={$t("settings.metadata.disable.title")}
+        description={$t("settings.metadata.disable.description")}
     />
 </SettingsCategory>
 
-<SettingsCategory title="saving method">
+<SettingsCategory title={$t("settings.saving.method")}>
     <SettingsToggle
         settingContext="save"
         settingId="downloadPopup"
-        title="ask how to save"
-        description="cobalt will offer you several ways to save the file instead of opening it in a new tab."
+        title={$t("settings.saving.ask.title")}
+        description={$t("settings.saving.ask.description")}
     />
 </SettingsCategory>