Merge commit '44cd88adc4e2f4028dcc2b08b98368f0dc90cee4' into glitch-soc/merge-upstream

Conflicts:
- `.github/dependabot.yml`:
  Updated upstream, but we've deleted it.
  Keep it deleted.
- `app/javascript/mastodon/locales/index.js`:
  Reworked upstream, but the code was mostly in
  `app/javascript/locales/index.js` in glitch-soc.
  Updated that file accordingly.
- `app/javascript/packs/public.jsx`:
  Not a real conflict, but different imports in
  glitch-soc and upstream.
- `app/views/layouts/application.html.haml`:
  Conflict due to locales loading and theme system
  discrepancies.
  Updated in our own way.
- `app/views/layouts/embedded.html.haml`:
  Conflict due to locales loading and theme system
  discrepancies.
  Updated in our own way.
- `config/webpack/generateLocalePacks.js`:
  Deleted upstream, as upstream now directly loads the
  JSON at runtime.
  Deleted as well, will switch to runtime loading in
  an upcoming commit.
- `config/webpack/shared.js`:
  Not a real conflict, but different imports in
  glitch-soc and upstream.
- `config/webpack/translationRunner.js`:
  Mostly deleted upstream, to be replaced with `formatjs-formatter.js`
  instead.
  Moved the glitch-soc logic there and deleted the file.

package.json

@@ -9,6 +9,7 @@
     "build:development": "cross-env RAILS_ENV=development NODE_ENV=development ./bin/webpack",
     "build:production": "cross-env RAILS_ENV=production NODE_ENV=production ./bin/webpack",
     "manage:translations": "node ./config/webpack/translationRunner.js",
+    "i18n:extract": "formatjs extract 'app/javascript/**/*.{js,jsx,ts,tsx}' '--ignore=**/*.d.ts' --out-file app/javascript/flavours/glitch/locales/en.json --format config/formatjs-formatter.js",
     "start": "node ./streaming/index.js",
     "test": "${npm_execpath} run test:lint:js && ${npm_execpath} run test:typecheck && ${npm_execpath} run test:jest",
     "test:lint": "${npm_execpath} run test:lint:js && ${npm_execpath} run test:lint:sass",
@@ -34,6 +35,7 @@
     "@babel/preset-react": "^7.22.3",
     "@babel/preset-typescript": "^7.21.5",
     "@babel/runtime": "^7.22.3",
+    "@formatjs/intl-pluralrules": "^5.2.2",
     "@gamestdio/websocket": "^0.3.2",
     "@github/webauthn-json": "^2.1.1",
     "@rails/ujs": "^6.1.7",
@@ -44,9 +46,9 @@
     "autoprefixer": "^10.4.14",
     "axios": "^1.4.0",
     "babel-loader": "^8.3.0",
+    "babel-plugin-formatjs": "^10.5.1",
     "babel-plugin-lodash": "^3.3.4",
     "babel-plugin-preval": "^5.1.0",
-    "babel-plugin-react-intl": "^6.2.0",
     "babel-plugin-transform-react-remove-prop-types": "^0.4.24",
     "blurhash": "^2.0.5",
     "classnames": "^2.3.2",
@@ -72,9 +74,7 @@
     "http-link-header": "^1.1.1",
     "immutable": "^4.3.0",
     "imports-loader": "^1.2.0",
-    "intl": "^1.2.5",
-    "intl-messageformat": "^2.2.0",
-    "intl-relativeformat": "^6.4.3",
+    "intl-messageformat": "^10.3.5",
     "js-yaml": "^4.1.0",
     "jsdom": "^22.1.0",
     "lodash": "^4.17.21",
@@ -96,7 +96,7 @@
     "react-hotkeys": "^1.1.4",
     "react-immutable-proptypes": "^2.2.0",
     "react-immutable-pure-component": "^2.2.2",
-    "react-intl": "^2.9.0",
+    "react-intl": "^6.4.2",
     "react-motion": "^0.5.2",
     "react-notification": "^6.8.5",
     "react-overlays": "^5.2.1",
@@ -142,6 +142,7 @@
     "ws": "^8.12.1"
   },
   "devDependencies": {
+    "@formatjs/cli": "^6.1.1",
     "@testing-library/jest-dom": "^5.16.5",
     "@testing-library/react": "^14.0.0",
     "@types/babel__core": "^7.20.1",
@@ -162,7 +163,6 @@
     "@types/react-dom": "^18.2.4",
     "@types/react-helmet": "^6.1.6",
     "@types/react-immutable-proptypes": "^2.1.0",
-    "@types/react-intl": "2.3.18",
     "@types/react-motion": "^0.0.34",
     "@types/react-overlays": "^3.1.0",
     "@types/react-router-dom": "^5.3.3",
@@ -196,7 +196,6 @@
     "jest-environment-jsdom": "^29.5.0",
     "lint-staged": "^13.2.2",
     "prettier": "^2.8.8",
-    "react-intl-translations-manager": "^5.0.3",
     "react-test-renderer": "^18.2.0",
     "stylelint": "^15.6.2",
     "stylelint-config-standard-scss": "^9.0.0",