Submission changes for better validation

submit.py

@@ -91,6 +91,7 @@ def make_submission(
     # if profile:
     #    user_state = profile.name
     validate_username(user_state)
+    username = user_state.strip()
 
     model_name = model_name.strip()
     model_description = model_description.strip()
@@ -139,7 +140,7 @@ def make_submission(
         # Upload submission without re-validating (already done)
         upload_submission(
             file_content=file_content,
-            user_state=user_state,
+            user_state=username,
             submission_type=submission_type,
             model_name=model_name,
             model_description=model_description,

validation.py

@@ -195,6 +195,11 @@ def validate_dataframe(df: pd.DataFrame, submission_type: str = "GDPa1") -> None
         missing_count = df[col].isnull().sum()
         if missing_count > 0:
             raise gr.Error(f"❌ Column '{col}' contains {missing_count} missing values")
+        
+    # No constant values in assay columns
+    for col in assay_columns:
+        if df[col].nunique() == 1:
+            raise gr.Error(f"❌ Column '{col}' contains a constant value ({df[col].iloc[0]}), and therefore the Spearman correlation is undefined.")
 
     # All names should be unique
     n_duplicates = df["antibody_name"].duplicated().sum()