fix: restore all code deleted/truncated by d2217531 Jules SSRF commit

Commit d2217531 (google-labs-jules SSRF fix) catastrophically deleted
11,500+ lines across 100+ files while fixing an unrelated IMAP issue.

Restored from d2217531^ (pre-bad-commit state):

Deleted files (fully restored):
- app/api/{automation,classification_rules,comments,sharing}.py
- app/middleware/upload_rate_limit.py
- app/tasks/{automation_tasks,classify_document}.py
- app/utils/{automation_hooks,classification_rules}.py
- docs/AppleAppStoreCompliance.md
- frontend/input.css, package.json, package-lock.json, tailwind.config.js
- frontend/static/js/{annotations,claim,comments,sharing}.js
- frontend/templates/{admin_connections,file_annotations,file_summary}.html
- tests/{test_api_files_comprehensive,test_auth_extended,test_sharing,
         test_comments,test_connections,test_imap_profiles,test_api_sessions,
         test_automation,test_classification_rules,test_api_advanced_filters,
         test_api_classification_rules,test_upload_rate_limit,test_api_dropbox,
         test_classify_document,test_comments_ui,test_upload_to_icloud,
         test_api_onedrive_comprehensive,test_frontend_build,test_sentry,
         test_diagnostic,test_database,test_views_dropbox,test_local_auth}.py

Truncated files (content restored):
- app/{auth,config,main,models,celery_worker,database}.py
- app/api/{__init__,api_tokens,diagnostic,dropbox,files,google_drive,
           integrations,local_auth,mobile,onedrive,pipelines,qr_auth,
           settings,url_upload}.py
- app/middleware/upload_rate_limit.py
- app/tasks/upload_to_nextcloud.py
- app/utils/{allowed_types,settings_service,settings_sync,user_scope,webhook}.py
- app/views/{base,dropbox,files,google_drive,onedrive,settings}.py
- docs/{API,AuthenticationSetup,ConfigurationGuide,DatabaseConfiguration,
        DeploymentGuide,DropboxSetup,GoogleDriveSetup,KubernetesDeployment,
        MobileApp,OneDriveSetup,ProductionReadiness,SentrySetup,
        SocialLoginSetup,UserGuide}.md
- frontend/static/{js/upload.js,styles.css}
- frontend/templates/{api_tokens,base,devices,dropbox,dropbox_callback,
                      file_view,files,google_drive,onedrive,onedrive_callback,
                      signup}.html
- frontend/translations/en.json
- migrations/env.py
- tests/{conftest,test_api_integrations,test_api_mobile,test_api_settings,
         test_api_tokens,test_audit_logs,test_duplicates,test_imap_tasks,
         test_setup_wizard,test_views_files_comprehensive}.py

Security fixes kept from post-d2217531 commits:
- app/utils/network.py: DNS SSRF fail-secure fix (06b0fced)
- app/utils/file_operations.py: path traversal fix (1018ea17)
- tests/test_imap_tasks.py: re-applied 4 is_private_ip mock patches

Co-authored-by: christianlouis <361235+christianlouis@users.noreply.github.com>
Agent-Logs-Url: https://github.com/christianlouis/DocuElevate/sessions/51133dd8-9bec-41ab-aa10-3de753634187

docs/AuthenticationSetup.md

@@ -15,6 +15,7 @@ This guide explains how to configure authentication for DocuElevate to secure yo
 | `AUTHENTIK_CLIENT_SECRET`  | Client secret for OpenID Connect authentication          |
 | `AUTHENTIK_CONFIG_URL`     | OpenID Connect discovery URL                             |
 | `OAUTH_PROVIDER_NAME`      | Display name for the OAuth provider button               |
+| `SSO_AUTO_LOGIN`           | Auto-redirect to SSO login (skips the login page)        |
 
 For a complete list of configuration options, see the [Configuration Guide](ConfigurationGuide.md).
 
@@ -24,7 +25,12 @@ DocuElevate supports multiple authentication methods that can be used independen
 
 1. **Simple Authentication** - Basic username/password authentication managed by DocuElevate
 2. **OpenID Connect** - Integration with identity providers like Authentik, Keycloak, or Auth0
-3. **Social Login** - Sign in with Google, Microsoft, Apple, or Dropbox accounts (see [Social Login Setup Guide](SocialLoginSetup.md))
+3. **Social Login** - Sign in with Google, Microsoft, Apple, Dropbox, or GitHub accounts (see [Social Login Setup Guide](SocialLoginSetup.md))
+4. **Keycloak SSO** - Self-hosted identity management via Keycloak
+5. **Generic OAuth2** - Any OAuth2-compatible identity provider
+6. **SAML2** - Enterprise SSO via SAML 2.0
+
+> **Admin Connections Page:** You can configure all authentication providers through the admin **Connections** page at `/admin/connections`.
 
 ## Session Security