feat(core): improve auth handling (#15271)

fix #15270
fix #15260
fix #15257


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* **PR #15271** 👈

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packages/frontend/admin/src/config.json

@@ -482,7 +482,7 @@
     },
     "providers.oidc": {
       "type": "Object",
-      "desc": "OIDC OAuth provider config",
+      "desc": "OIDC OAuth provider config. Private network access requires allowPrivateNetwork: true",
       "link": "https://openid.net/specs/openid-connect-core-1_0.html"
     },
     "providers.apple": {