Merge branch 'main' into glitch-soc/merge-upstream

Conflicts:
- `.env.production.sample`:
  Upstream added new configuration options, uncommented by default.
  Commented them.
- `Gemfile.lock`:
  Upstream updated dependencies textually close to glitch-soc-specific
  dependencies.
  Updated those upstream dependencies.

app/javascript/mastodon/locales/en.json

@@ -47,11 +47,16 @@
   "account.unmute": "Unmute @{name}",
   "account.unmute_notifications": "Unmute notifications from @{name}",
   "account_note.placeholder": "Click to add note",
+  "admin.dashboard.retention": "Retention",
+  "admin.dashboard.retention.average": "Average",
+  "admin.dashboard.retention.cohort": "Sign-up month",
+  "admin.dashboard.retention.cohort_size": "New users",
   "alert.rate_limited.message": "Please retry after {retry_time, time, medium}.",
   "alert.rate_limited.title": "Rate limited",
   "alert.unexpected.message": "An unexpected error occurred.",
   "alert.unexpected.title": "Oops!",
   "announcement.announcement": "Announcement",
+  "attachments_list.unprocessed": "(unprocessed)",
   "autosuggest_hashtag.per_week": "{count} per week",
   "boost_modal.combo": "You can press {combo} to skip this next time",
   "bundle_column_error.body": "Something went wrong while loading this component.",
@@ -117,6 +122,8 @@
   "confirmations.delete.message": "Are you sure you want to delete this post?",
   "confirmations.delete_list.confirm": "Delete",
   "confirmations.delete_list.message": "Are you sure you want to permanently delete this list?",
+  "confirmations.discard_edit_media.confirm": "Discard",
+  "confirmations.discard_edit_media.message": "You have unsaved changes to the media description or preview, discard them anyway?",
   "confirmations.domain_block.confirm": "Block entire domain",
   "confirmations.domain_block.message": "Are you really, really sure you want to block the entire {domain}? In most cases a few targeted blocks or mutes are sufficient and preferable. You will not see content from that domain in any public timelines or your notifications. Your followers from that domain will be removed.",
   "confirmations.logout.confirm": "Log out",
@@ -344,6 +351,7 @@
   "poll.total_votes": "{count, plural, one {# vote} other {# votes}}",
   "poll.vote": "Vote",
   "poll.voted": "You voted for this answer",
+  "poll.votes": "{votes, plural, one {# vote} other {# votes}}",
   "poll_button.add_poll": "Add a poll",
   "poll_button.remove_poll": "Remove poll",
   "privacy.change": "Change post privacy",
@@ -459,6 +467,7 @@
   "upload_form.video_description": "Describe for people with hearing loss or visual impairment",
   "upload_modal.analyzing_picture": "Analyzing picture…",
   "upload_modal.apply": "Apply",
+  "upload_modal.applying": "Applying…",
   "upload_modal.choose_image": "Choose image",
   "upload_modal.description_placeholder": "A quick brown fox jumps over the lazy dog",
   "upload_modal.detect_text": "Detect text from picture",