Saml fix (#5651)

# Description of Changes
When password login is disabled UI changes to have central style SSO
button

<img width="2057" height="1369" alt="image"
src="https://github.com/user-attachments/assets/8f65f778-0809-4c54-a9c4-acf3a67cfa63"
/>

Auto SSO login functionality

Massively increases auth debugging visibility: verbose console logging
in ErrorBoundary, AuthProvider, Landing, AuthCallback.

Improves OAuth/SAML testability: adds Keycloak docker-compose setups +
realm JSON exports + start/validate scripts for OAuth and SAML
environments.

Hardens license upload path handling: better logs + safer directory
traversal protection by normalizing absolute paths before startsWith
check.

UI polish for SSO-only login: new “single provider” centered layout +
updated button styles (pill buttons, variants, icon wrapper, arrow).


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- Why the change was made
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---

## Checklist

### General

- [ ] I have read the [Contribution
Guidelines](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/CONTRIBUTING.md)
- [ ] I have read the [Stirling-PDF Developer
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md)
(if applicable)
- [ ] I have read the [How to add new languages to
Stirling-PDF](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md)
(if applicable)
- [ ] I have performed a self-review of my own code
- [ ] My changes generate no new warnings

### Documentation

- [ ] I have updated relevant docs on [Stirling-PDF's doc
repo](https://github.com/Stirling-Tools/Stirling-Tools.github.io/blob/main/docs/)
(if functionality has heavily changed)
- [ ] I have read the section [Add New Translation
Tags](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/HowToAddNewLanguage.md#add-new-translation-tags)
(for new translation tags only)

### Translations (if applicable)

- [ ] I ran
[`scripts/counter_translation.py`](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/docs/counter_translation.md)

### UI Changes (if applicable)

- [ ] Screenshots or videos demonstrating the UI changes are attached
(e.g., as comments or direct attachments in the PR)

### Testing (if applicable)

- [ ] I have tested my changes locally. Refer to the [Testing
Guide](https://github.com/Stirling-Tools/Stirling-PDF/blob/main/devGuide/DeveloperGuide.md#6-testing)
for more details.

testing/compose/keycloak-realm-oauth.json

@@ -0,0 +1,370 @@
+{
+  "id": "stirling-oauth",
+  "realm": "stirling-oauth",
+  "displayName": "Stirling PDF OAuth Test",
+  "displayNameHtml": "<div class=\"kc-logo-text\"><span>Stirling PDF OAuth</span></div>",
+  "enabled": true,
+  "sslRequired": "none",
+  "registrationAllowed": true,
+  "registrationEmailAsUsername": true,
+  "rememberMe": true,
+  "verifyEmail": false,
+  "loginWithEmailAllowed": true,
+  "duplicateEmailsAllowed": false,
+  "resetPasswordAllowed": true,
+  "editUsernameAllowed": false,
+  "bruteForceProtected": false,
+  "accessTokenLifespan": 300,
+  "accessTokenLifespanForImplicitFlow": 900,
+  "ssoSessionIdleTimeout": 1800,
+  "ssoSessionMaxLifespan": 36000,
+  "offlineSessionIdleTimeout": 2592000,
+  "users": [
+    {
+      "username": "[email protected]",
+      "email": "[email protected]",
+      "emailVerified": true,
+      "firstName": "OAuth",
+      "lastName": "TestUser",
+      "enabled": true,
+      "credentials": [
+        {
+          "type": "password",
+          "value": "oauthpassword",
+          "temporary": false
+        }
+      ],
+      "realmRoles": ["user"],
+      "attributes": {
+        "phone": ["+1234567890"],
+        "organization": ["Test Corp"]
+      }
+    },
+    {
+      "username": "[email protected]",
+      "email": "[email protected]",
+      "emailVerified": true,
+      "firstName": "OAuth",
+      "lastName": "Admin",
+      "enabled": true,
+      "credentials": [
+        {
+          "type": "password",
+          "value": "oauthadminpass",
+          "temporary": false
+        }
+      ],
+      "realmRoles": ["user", "admin"],
+      "attributes": {
+        "phone": ["+1987654321"],
+        "organization": ["Test Corp IT"]
+      }
+    }
+  ],
+  "roles": {
+    "realm": [
+      {
+        "name": "user",
+        "description": "Regular user role",
+        "composite": false,
+        "clientRole": false
+      },
+      {
+        "name": "admin",
+        "description": "Administrator role",
+        "composite": false,
+        "clientRole": false
+      }
+    ]
+  },
+  "clients": [
+    {
+      "clientId": "stirling-pdf-client",
+      "name": "Stirling PDF OAuth2 Client",
+      "description": "OAuth2/OIDC client for Stirling PDF testing",
+      "rootUrl": "http://localhost:8080",
+      "adminUrl": "http://localhost:8080",
+      "baseUrl": "http://localhost:8080",
+      "enabled": true,
+      "clientAuthenticatorType": "client-secret",
+      "secret": "test-client-secret-change-in-production",
+      "redirectUris": [
+        "http://localhost:8080/*",
+        "http://localhost:8080/login/oauth2/code/keycloak",
+        "http://stirling-pdf-oauth:8080/*",
+        "http://stirling-pdf-oauth:8080/login/oauth2/code/keycloak"
+      ],
+      "webOrigins": [
+        "http://localhost:8080",
+        "http://stirling-pdf-oauth:8080"
+      ],
+      "bearerOnly": false,
+      "consentRequired": false,
+      "standardFlowEnabled": true,
+      "implicitFlowEnabled": false,
+      "directAccessGrantsEnabled": true,
+      "serviceAccountsEnabled": false,
+      "publicClient": false,
+      "frontchannelLogout": false,
+      "protocol": "openid-connect",
+      "attributes": {
+        "oidc.ciba.grant.enabled": "false",
+        "backchannel.logout.session.required": "true",
+        "oauth2.device.authorization.grant.enabled": "false",
+        "display.on.consent.screen": "false",
+        "backchannel.logout.revoke.offline.tokens": "false"
+      },
+      "fullScopeAllowed": true,
+      "protocolMappers": [
+        {
+          "name": "email",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "email",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "email",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "email_verified",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "emailVerified",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "email_verified",
+            "jsonType.label": "boolean"
+          }
+        },
+        {
+          "name": "given_name",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "firstName",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "given_name",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "family_name",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "lastName",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "family_name",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "preferred_username",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "username",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "preferred_username",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "roles",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-realm-role-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "roles",
+            "jsonType.label": "String",
+            "multivalued": "true"
+          }
+        }
+      ],
+      "defaultClientScopes": [
+        "web-origins",
+        "acr",
+        "profile",
+        "roles",
+        "email"
+      ],
+      "optionalClientScopes": [
+        "address",
+        "phone",
+        "offline_access",
+        "microprofile-jwt"
+      ]
+    }
+  ],
+  "clientScopes": [
+    {
+      "name": "email",
+      "description": "OpenID Connect built-in scope: email",
+      "protocol": "openid-connect",
+      "attributes": {
+        "include.in.token.scope": "true",
+        "display.on.consent.screen": "true"
+      },
+      "protocolMappers": [
+        {
+          "name": "email",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "email",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "email",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "email verified",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "emailVerified",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "email_verified",
+            "jsonType.label": "boolean"
+          }
+        }
+      ]
+    },
+    {
+      "name": "profile",
+      "description": "OpenID Connect built-in scope: profile",
+      "protocol": "openid-connect",
+      "attributes": {
+        "include.in.token.scope": "true",
+        "display.on.consent.screen": "true"
+      },
+      "protocolMappers": [
+        {
+          "name": "given name",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "firstName",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "given_name",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "family name",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "lastName",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "family_name",
+            "jsonType.label": "String"
+          }
+        },
+        {
+          "name": "username",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-property-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "user.attribute": "username",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "preferred_username",
+            "jsonType.label": "String"
+          }
+        }
+      ]
+    },
+    {
+      "name": "roles",
+      "description": "OpenID Connect scope for user roles",
+      "protocol": "openid-connect",
+      "attributes": {
+        "include.in.token.scope": "true",
+        "display.on.consent.screen": "true"
+      },
+      "protocolMappers": [
+        {
+          "name": "realm roles",
+          "protocol": "openid-connect",
+          "protocolMapper": "oidc-usermodel-realm-role-mapper",
+          "consentRequired": false,
+          "config": {
+            "userinfo.token.claim": "true",
+            "id.token.claim": "true",
+            "access.token.claim": "true",
+            "claim.name": "roles",
+            "jsonType.label": "String",
+            "multivalued": "true"
+          }
+        }
+      ]
+    }
+  ],
+  "defaultDefaultClientScopes": [
+    "role_list",
+    "profile",
+    "email",
+    "roles",
+    "web-origins",
+    "acr"
+  ],
+  "defaultOptionalClientScopes": [
+    "offline_access",
+    "address",
+    "phone",
+    "microprofile-jwt"
+  ],
+  "browserSecurityHeaders": {
+    "contentSecurityPolicyReportOnly": "",
+    "xContentTypeOptions": "nosniff",
+    "referrerPolicy": "no-referrer",
+    "xRobotsTag": "none",
+    "xFrameOptions": "SAMEORIGIN",
+    "contentSecurityPolicy": "frame-src 'self'; frame-ancestors 'self'; object-src 'none';",
+    "xXSSProtection": "1; mode=block",
+    "strictTransportSecurity": "max-age=31536000; includeSubDomains"
+  },
+  "eventsEnabled": false,
+  "eventsListeners": ["jboss-logging"],
+  "enabledEventTypes": [],
+  "adminEventsEnabled": false,
+  "adminEventsDetailsEnabled": false,
+  "internationalizationEnabled": false,
+  "supportedLocales": [],
+  "keycloakVersion": "24.0.0"
+}