feat: add Azure DevOps enterprise integration support

[zerofltexx]

Add Azure DevOps Enterprise Integration Support

Add support for Azure DevOps as an enterprise identity provider with automatic organization discovery. The
integration uses Azure AD app registration for authentication and automatically discovers user organizations
via the Azure DevOps Accounts API. This is to support OpenHands/OpenHands/pull/11667

Changes:

• Add azureDevOps configuration to values.yaml with tenant ID and secret support
• Add Azure DevOps environment variables and keycloak configuration
• Add ingress route for Azure DevOps integration endpoint
• Update README with Azure DevOps setup instructions including secret configuration
• Use auto-discovery for organizations instead of manual configuration

Description

This PR adds Azure DevOps as a supported enterprise identity provider, following the same integration pattern
as existing providers (GitHub, GitLab, BitBucket).

Key Features:

• Automatic Organization Discovery: Users' Azure DevOps organizations are automatically discovered via the
  Azure DevOps Accounts API, eliminating the need for manual configuration
• Multi-tenant Support: Supports both single-tenant and multi-tenant Azure AD applications through the
  configurable tenantId field
• Keycloak Integration: Fully integrated with the existing Keycloak authentication flow

Implementation Details:

• The integration uses Azure AD app registration for OAuth authentication
• Organization discovery happens automatically when users authenticate - the system queries the Azure DevOps
  Accounts API
• The configuration includes a dedicated Kubernetes secret (azuredevops-app) for storing client credentials
• Added ingress route /integration/azuredevops/* for Azure DevOps-specific endpoints

Helm Chart Checklist

• I have updated the version field in Chart.yaml for each modified chart
• I have tested the chart upgrade path from the previous version
• I have verified backwards compatibility with existing values.yaml configurations
• I have updated the chart's README.md if there are any breaking changes or new required values

Additional Notes

Backwards Compatibility:
This change is fully backwards compatible. The Azure DevOps integration is disabled by default
(azureDevOps.enabled: false) and requires explicit configuration to enable.

Documentation:
Complete setup instructions have been added to the README, including:

• Step-by-step Azure AD app registration process
• Kubernetes secret creation commands
• Example site-values.yaml configuration with all required fields

Testing:
To test this integration, you'll need:

1. An Azure AD tenant with app registration permissions
2. Access to an Azure DevOps organization
3. The ability to create Kubernetes secrets in your test environment