Feature Request: Add "Upload File" Support for Azure Key Vault Secrets

Azure Key Vault supports multiline secrets and the official documentation recommends using a file when storing them. However, the Azure Portal only provides a manual text entry field when creating secrets. This creates an inconsistent user experience because common assets such as PEM certificate chains, SSH keys, JSON configurations, or other multiline secrets require the use of Azure CLI (az keyvault secret set --file) instead of the Portal. A native "Upload file as secret" capability in the Portal would improve usability and reduce formatting-related issues.