fix: address Cubic findings for FreeUsageLimitError classification

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/shared/model-error-classifier.test.ts

@@ -83,7 +83,7 @@ describe("model-error-classifier", () => {
     expect(provider).toBe("provider-x")
   })
 
-  test("treats FreeUsageLimitError (lowercase) as retryable by name", () => {
+  test("treats FreeUsageLimitError (PascalCase name) as retryable by name", () => {
     //#given
     const error = { name: "FreeUsageLimitError" }