feat: update changelog for version 1.4.0 with new features and fixes

feat: update README.md to reflect version 1.4.0 and new features
chore: bump version to 1.4.0 in VERSION and package files
feat: implement identity refresh behavior in identity management
feat: add TNEF support for Outlook emails and archive organization modes
feat: enhance UI with configurable sidebar apps and branding options
refactor: remove unused addon-plugin-theme-concept.md file

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "bulwark-webmail",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "bulwark-webmail",
-      "version": "1.3.0",
+      "version": "1.4.0",
       "license": "AGPL-3.0-only",
       "dependencies": {
         "@tanstack/react-virtual": "^3.13.18",