Remove OAuthToken from db (use authlib dict); basic OAuth2 service provider with Forgejo

src/oidc_test/templates/home.html

@@ -109,6 +109,8 @@
       <a href="protected-by-foorole-and-barrole">Auth + foorole and barrole protected content</a>
       <a href="fast_api_depends" class="hidden">Using FastAPI Depends</a>
       <a href="other">Other</a>
+      <a href="oauth2-forgejo-test">OAuth2 test (forgejo user info)</a>
+      <a href="introspect">Introspect token</a>
     </div>
   {% if user_info_details %}
     <div class="debug-auth">