Update README and refine UI elements and localization

This commit introduces updates to the README file, specifically focusing on authentication emails. Minor UI adjustments have been made to various layout spacings and image attributes in some pages for better design consistency. Localization has also been improved by introducing translation keys for error and not-found pages in the common JSON file.

apps/web/public/locales/en/common.json

@@ -48,18 +48,14 @@
   "signedInAs": "Signed in as",
   "pageOfPages": "Page {{page}} of {{total}}",
   "noData": "No data available",
+  "pageNotFoundHeading": "Ouch! :|",
+  "errorPageHeading": "Ouch! :|",
   "roles": {
     "owner": {
-      "label": "Owner",
-      "description": "Can change any setting, invite new members and manage billing"
-    },
-    "admin": {
-      "label": "Admin",
-      "description": "Can change some settings, invite members, perform disruptive actions"
+      "label": "Owner"
     },
     "member": {
-      "label": "Member",
-      "description": "Cannot invite members or change settings"
+      "label": "Member"
     }
   }
 }