[Azure Backup][Namespace] Failed to trigger mcp tools

**Description:**
In `Namespace` mode, testing prompts related to [Azure Backup](https://github.com/microsoft/mcp/blob/main/servers/Azure.Mcp.Server/docs/e2eTestPrompts.md#azure-backup).
With prompts:
- Enable cross-region restore on vault in resource group
- Turn on cross-region restore for vault under resource group

Bot will rather call `azurebackup_vault_update` instead of `azurebackup_disasterrecovery_enable-crr`.

With prompts:
- Find unprotected resources of type keyvault in my subscription
- Show me Azure resources that are not backed up for resource type keyvault
- Find unprotected SQL databases and file shares discovered by backup vaults in my subscription
- Find all resources and sub-resources in resource group chenjiang-mcp-test that are not protected by Azure Backup

Bot failed to trigger `azurebackup_governance_find-unprotected` in the conversation.

With prompts:
- Configure immutability state on vault chengjiangrs in resource group chenjiang-mcp-test
- Set immutability to Enabled on vault chengjiangrs in resource group chenjiang-mcp-test

Bot failed to trigger `azurebackup_governance_immutability` in the conversation.

With prompts:
- Configure soft delete on Azure Backup vault chengjiangrs in resource group chenjiang-mcp-test
- Set soft delete state to AlwaysOn for vault chengjiangrs in resource group chenjiang-mcp-test

Bot failed to trigger `azurebackup_governance_soft-delete` in the conversation.

**Steps to Reproduce:**
1. Start mcp server in `Namespace` mode.
2. Open GitHub Copilot in VS Code and [switch to Agent mode](https://code.visualstudio.com/docs/copilot/chat/chat-agent-mode).
3. Enter the test prompt.

**Environment:**
- OS: Windows.
- Vscode Version: 1.134
- Large Language Model: **GPT-5.6 Sol**
- Azure MCP Server: **3.0.37**

**Expected Behavior:**
The mcp tools could be triggered successfully in namespace mode.

@RickWinter and @g2vinay for notification