Plugin architecture (#4861)

* wip

* Refactor, tasks, processors, routes loading

* Move Slack settings config to plugin

* Fix translations in plugins

* Move Slack auth to plugin

* test

* Move other slack-related files into plugin

* Forgot to save

* refactor

package.json

@@ -6,7 +6,7 @@
   "scripts": {
     "clean": "rimraf build",
     "copy:i18n": "mkdir -p ./build/shared/i18n && cp -R ./shared/i18n/locales ./build/shared/i18n",
-    "build:i18n": "i18next --silent 'shared/**/*.tsx' 'shared/**/*.ts' 'app/**/*.tsx' 'app/**/*.ts' 'server/**/*.ts' 'server/**/*.tsx' && yarn copy:i18n",
+    "build:i18n": "i18next --silent '{shared,app,server,plugins}/**/*.{ts,tsx}' && yarn copy:i18n",
     "build:server": "./build.sh",
     "build:webpack": "webpack --config webpack.config.prod.js",
     "build": "yarn clean && yarn build:webpack && yarn build:i18n && yarn build:server",
@@ -100,6 +100,7 @@
     "fs-extra": "^4.0.2",
     "fuzzy-search": "^3.2.1",
     "gemoji": "6.x",
+    "glob": "^8.1.0",
     "http-errors": "2.0.0",
     "i18next": "^22.4.8",
     "i18next-fs-backend": "^2.1.1",
@@ -240,6 +241,7 @@
     "@types/formidable": "^2.0.5",
     "@types/fs-extra": "^9.0.13",
     "@types/fuzzy-search": "^2.1.2",
+    "@types/glob": "^8.0.1",
     "@types/google.analytics": "^0.0.42",
     "@types/inline-css": "^3.0.1",
     "@types/invariant": "^2.2.35",