support 1p (#7945)

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codex-rs/core/src/openai_models/model_family.rs

@@ -264,7 +264,7 @@ pub(super) fn find_family_for_model(slug: &str) -> ModelFamily {
         )
 
     // Experimental models.
-    } else if slug.starts_with("exp-codex") {
+    } else if slug.starts_with("exp-codex") || slug.starts_with("codex-1p") {
         // Same as gpt-5.1-codex-max.
         model_family!(
             slug, slug,