style: fix ruff SIM102 and PERF203 warnings

- Combine nested if statements in fill_links_from_history (SIM102)
- Extract validate_conference helper to avoid try-except in loop (PERF203)

Author: claude

utils/import_python_official.py

@@ -66,10 +66,13 @@ def fill_links_from_history(df_ics: pd.DataFrame, df_yml: pd.DataFrame) -> pd.Da
         link = row.get("link", "")
         year = row.get("year", 0)
 
-        if conf_name and link:
-            # Keep the most recent link for each conference
-            if conf_name not in historical_links or year > historical_links[conf_name][1]:
-                historical_links[conf_name] = (link, year)
+        # Keep the most recent link for each conference
+        if (
+            conf_name
+            and link
+            and (conf_name not in historical_links or year > historical_links[conf_name][1])
+        ):
+            historical_links[conf_name] = (link, year)
 
     filled_count = 0
     for idx, row in df_ics.iterrows():

utils/sort_yaml.py

@@ -301,17 +301,19 @@ def sort_data(base="", prefix="", skip_links=False):
     for i, q in enumerate(data.copy()):
         data[i] = order_keywords(q)
 
-    logger.info("✅ Validating conference data with Pydantic schema")
-    new_data = []
-    validation_errors = 0
-
-    for q in data:
+    def validate_conference(q: dict) -> Conference | None:
+        """Validate a single conference entry, returning None if invalid."""
         try:
-            new_data.append(Conference(**q))
+            return Conference(**q)
         except pydantic.ValidationError as e:
-            validation_errors += 1
             logger.error(f"❌ Validation error in conference: {e}")
             logger.debug(f"Invalid data: \n{yaml.dump(q, default_flow_style=False)}")
+            return None
+
+    logger.info("✅ Validating conference data with Pydantic schema")
+    validated = [validate_conference(q) for q in data]
+    new_data = [c for c in validated if c is not None]
+    validation_errors = len(validated) - len(new_data)
 
     if validation_errors > 0:
         logger.warning(f"⚠️  {validation_errors} conferences failed validation and were skipped")