feat(server): added backchannel logout api endpoint (#26235)

* feat(server): added backchannel logout api endpoint

* test(server): fixed e2e tests

* fix(server): fixed suggested changes by reviewer

* feat(server): created function invalidateOAuth

* fix(server): fixed session.repository.sql

* test(server): added unit tests for backchannelLogout function

* test(server): added e2e tests for oidc backchnnel logout

* docs(server): added documentation on backchannel logout url

* docs(server): fixed typo

* feat(server): minor improvements of the oidc backchannel logout

* test(server): fixed tests after merge with main

* fix(server): fixed e2e test file

* refactor(server): tiny refactor of validateLogoutToken

* chore: cleanup

* fix: tests

* fix: make jwks extractable

---------

Co-authored-by: Daniel Dietzler <mail@ddietzler.dev>

server/src/app.common.ts

@@ -1,5 +1,5 @@
 import { NestExpressApplication } from '@nestjs/platform-express';
-import { json } from 'body-parser';
+import { json, urlencoded } from 'body-parser';
 import compression from 'compression';
 import cookieParser from 'cookie-parser';
 import helmetMiddleware from 'helmet';
@@ -56,6 +56,7 @@ export async function configureExpress(
 
   app.use(cookieParser());
   app.use(json({ limit: '10mb' }));
+  app.use(urlencoded({ limit: '10mb' }));
 
   if (configRepository.isDev()) {
     app.enableCors();