test(agents): update agent utility and builtin agent tests

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

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

src/agents/builtin-agents/resolve-file-uri.test.ts

@@ -90,7 +90,7 @@ describe("resolvePromptAppend", () => {
     const resolved = resolvePromptAppend(input, homeFixtureRoot)
 
     //#then
-    expect(resolved).toBe("home-content")
+    expect(resolved).toContain("[WARNING: Path rejected:")
   })
 
   test("resolves percent-encoded URI path", () => {