Add sticky sessions to main README documentation

- Add Sticky Sessions guide to documentation table
- Add enable_sticky_sessions to Terraform Variables table

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: surinderunitone

README.md

@@ -29,6 +29,7 @@ This wrapper provides one-click Azure deployment:
 | [Production Setup](docs/PRODUCTION_SETUP.md) | Deploy to Azure step-by-step |
 | [Authentication](docs/AUTHENTICATION.md) | Configure OAuth and mTLS |
 | [Security Guards](docs/SECURITY_GUARDS.md) | Configure protection policies |
+| [Sticky Sessions](docs/STICKY_SESSIONS.md) | Multi-replica session affinity |
 | [Build Options](docs/BUILD_OPTIONS.md) | ACR vs VM build methods |
 
 ## Quick Start
@@ -230,6 +231,7 @@ binds:
 | `resource_group_name` | Azure resource group | Yes |
 | `location` | Azure region | No (default: eastus2) |
 | `configure_auth` | Enable Easy Auth | No (default: false) |
+| `enable_sticky_sessions` | Session affinity for multi-replica | No (default: true) |
 | `microsoft_client_id` | Azure AD OAuth | No |
 | `google_client_id` | Google OAuth | No |
 | `github_client_id` | GitHub OAuth | No |