fix: Load SELECT fields when using date functions in FT.AGGREGATE

When queries use date functions (YEAR, MONTH, etc.) alongside regular fields
in SELECT, the translator now properly loads those fields using LOAD clause.

Before: FT.AGGREGATE events "*" APPLY year(@created_at) AS year
After:  FT.AGGREGATE events "*" LOAD 1 name APPLY year(@created_at) AS year

Author: nkanu17

sql_redis/translator.py

@@ -252,6 +252,10 @@ def _build_aggregate(
                 load_fields.add(agg.field)
         for field_name in analyzed.groupby_fields:
             load_fields.add(field_name)
+        # Load explicit SELECT fields when using date functions
+        for field_name in parsed.fields:
+            if field_name != "*":
+                load_fields.add(field_name)
 
         if load_fields:
             args.append("LOAD")