fix: satisfy codex lint checks

Author: Mateusz

internal/plugins/backends/openaicodex/managed_oauth_internal_test.go

@@ -360,7 +360,7 @@ func TestSelectAccountForSession_roundRobinSkipsCooldown(t *testing.T) {
 	}
 	store.markRateLimited(first, now.Add(time.Hour))
 
-	for i := 0; i < 3; i++ {
+	for i := range 3 {
 		acct, err := store.selectAccountForSession("")
 		if err != nil {
 			t.Fatal(err)

internal/plugins/backends/openaicodex/stream_internal_test.go

@@ -114,7 +114,7 @@ func TestUsageEstimatingStream_completedWithoutUsage_generatesEstimatedUsageBefo
 		}
 		events = append(events, ev)
 	}
-	var usageIdx, finishedIdx = -1, -1
+	usageIdx, finishedIdx := -1, -1
 	for i, ev := range events {
 		switch ev.Kind {
 		case lipapi.EventUsageDelta:

internal/plugins/backends/openaicodex/usage_estimator_test.go

@@ -60,7 +60,7 @@ func TestEstimateUsage_imageRefURL_usesConservativeDefault(t *testing.T) {
 			Role: lipapi.RoleUser,
 			Parts: []lipapi.Part{
 				lipapi.TextPart("describe"),
-				lipapi.Part{Kind: lipapi.PartImageRef, ImageRef: "https://example.com/image.png"},
+				{Kind: lipapi.PartImageRef, ImageRef: "https://example.com/image.png"},
 			},
 		}},
 	}