update Azure OpenAI model from gpt-4o to gpt-4.1 (#88)

Co-authored-by: GitHub Copilot (Claude Sonnet 4) <noreply@github.com>

Author: ferantivero

README.md

@@ -86,7 +86,7 @@ Follow these instructions to deploy this example to your Azure subscription, try
     - App Service Plans: P1v3 (AZ), 3 instances
     - Azure AI Search (S - Standard): 1
     - Azure Cosmos DB: 1 account
-    - OpenAI model: GPT-4o model deployment with 50k tokens per minute (TPM) capacity
+    - OpenAI model: GPT-4.1 model deployment with 50k tokens per minute (TPM) capacity
     - DDoS Protection Plans: 1
     - Public IPv4 Addresses - Standard: 4
     - Standard DSv3 Family vCPU: 2

infra-as-code/bicep/ai-foundry.bicep

@@ -100,8 +100,8 @@ resource foundry 'Microsoft.CognitiveServices/accounts@2025-10-01-preview' = {
     properties: {
       model: {
         format: 'OpenAI'
-        name: 'gpt-4o'
-        version: '2024-11-20'  // Use a model version available in your region.
+        name: 'gpt-4.1'
+        version: '2025-04-14'  // Use a model version available in your region.
       }
       versionUpgradeOption: 'NoAutoUpgrade' // Production deployments should not auto-upgrade models.  Testing compatibility is important.
       raiPolicyName: 'Microsoft.DefaultV2'  // If this isn't strict enough for your use case, create a custom RAI policy.