chore: fix experimental flag

Signed-off-by: benjdlambert <ben@blam.sh>

.changeset/eleven-doors-down.md

@@ -2,4 +2,4 @@
 '@backstage/plugin-mcp-actions-backend': patch
 ---
 
-Proxy `/.well-known/oauth-authorization-server` to `/.well-known/openid-configuration` on `auth-backend` when `auth.experimental.enableDynamicClientRegistration` is enabled.
+Proxy `/.well-known/oauth-authorization-server` to `/.well-known/openid-configuration` on `auth-backend` when `auth.experimentalDynamicClientRegistration.enabled` is enabled.

.changeset/eleven-doors-own.md

@@ -2,4 +2,4 @@
 '@backstage/plugin-auth-backend': patch
 ---
 
-Implementing Dynamic Client Registration with the OIDC server. You can enable this by setting `auth.experimental.enableDynamicClientRegistration` in `app-config.yaml`. This is highly experimental, but feedback welcome.
+Implementing Dynamic Client Registration with the OIDC server. You can enable this by setting `auth.experimentalDynamicClientRegistration.enabled` in `app-config.yaml`. This is highly experimental, but feedback welcome.

plugins/auth-backend/src/service/router.ts

@@ -164,7 +164,7 @@ export async function createRouter(
     httpAuth,
     enableDynamicClientRegistration:
       config.getOptionalBoolean(
-        'auth.experimental.enableDynamicClientRegistration',
+        'auth.experimentalDynamicClientRegistration.enabled',
       ) ?? false,
   });
 

plugins/mcp-actions-backend/src/plugin.ts

@@ -81,7 +81,7 @@ export const mcpPlugin = createBackendPlugin({
 
         if (
           config.getOptionalBoolean(
-            'auth.experimental.enableDynamicClientRegistration',
+            'auth.experimentalDynamicClientRegistration.enabled',
           )
         ) {
           // This should be replaced with throwing a WWW-Authenticate header, but that doesn't seem to be supported by