Capitalize provider names in tool tips (#5981)

## Test plan

Manual testing + CI

Before:

![image](https://github.com/user-attachments/assets/82d85b8b-05a5-4e35-8fcd-9416edde5580)

After:

![image](https://github.com/user-attachments/assets/30995b5d-091f-41dd-a597-659f90f61424)

vscode/webviews/components/modelSelectField/ModelSelectField.tsx

@@ -315,13 +315,17 @@ function getTooltip(model: Model, availability: string): string {
         return 'Request received, we will reach out with next steps'
     }
 
+    const capitalizedProvider =
+        model.provider === 'openai'
+            ? 'OpenAI'
+            : model.provider.charAt(0).toUpperCase() + model.provider.slice(1)
     switch (availability) {
         case 'not-selectable-on-enterprise':
             return 'Chat model set by your Sourcegraph Enterprise admin'
         case 'needs-cody-pro':
-            return `Upgrade to Cody Pro to use ${model.title} by ${model.provider}`
+            return `Upgrade to Cody Pro to use ${model.title} by ${capitalizedProvider}`
         default:
-            return `${model.title} by ${model.provider}`
+            return `${model.title} by ${capitalizedProvider}`
     }
 }