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

Conflicts:
- `README.md`:
  Upstream README has been changed, but we have a completely different one.
  Kept our `README.md`.
- `lib/sanitize_ext/sanitize_config.rb`:
  Upstream added support for more incoming HTML tags (a large subset of what
  glitch-soc accepts).
  Change the code style to match upstream's but otherwise do not change our
  code.
- `spec/lib/sanitize_config_spec.rb`:
  Upstream added support for more incoming HTML tags (a large subset of what
  glitch-soc accepts).
  Kept our version, since the tests are mostly glitch-soc's, except for cases
  which are purposefuly different.

spec/policies/status_policy_spec.rb

@@ -39,6 +39,14 @@ RSpec.describe StatusPolicy, type: :model do
       expect(subject).to permit(alice, status)
     end
 
+    it 'grants access when direct and non-owner viewer is mentioned and mentions are loaded' do
+      status.visibility = :direct
+      status.mentions = [Fabricate(:mention, account: bob)]
+      status.mentions.load
+
+      expect(subject).to permit(bob, status)
+    end
+
     it 'denies access when direct and viewer is not mentioned' do
       viewer = Fabricate(:account)
       status.visibility = :direct