fix: Add column name aliases for MySQL information_schema queries

MySQL's information_schema columns are uppercase (COLUMN_NAME), but
PostgreSQL's are lowercase (column_name). Added explicit aliases to
get_primary_key_sql() and get_foreign_keys_sql() to ensure consistent
lowercase column names across both backends.

This fixes KeyError: 'column_name' in CI tests.

Author: dimitri-yatsenko

src/datajoint/adapters/mysql.py

@@ -577,7 +577,7 @@ def get_columns_sql(self, schema_name: str, table_name: str) -> str:
     def get_primary_key_sql(self, schema_name: str, table_name: str) -> str:
         """Query to get primary key columns."""
         return (
-            f"SELECT column_name FROM information_schema.key_column_usage "
+            f"SELECT COLUMN_NAME as column_name FROM information_schema.key_column_usage "
             f"WHERE table_schema = {self.quote_string(schema_name)} "
             f"AND table_name = {self.quote_string(table_name)} "
             f"AND constraint_name = 'PRIMARY' "
@@ -587,7 +587,8 @@ def get_primary_key_sql(self, schema_name: str, table_name: str) -> str:
     def get_foreign_keys_sql(self, schema_name: str, table_name: str) -> str:
         """Query to get foreign key constraints."""
         return (
-            f"SELECT constraint_name, column_name, referenced_table_name, referenced_column_name "
+            f"SELECT CONSTRAINT_NAME as constraint_name, COLUMN_NAME as column_name, "
+            f"REFERENCED_TABLE_NAME as referenced_table_name, REFERENCED_COLUMN_NAME as referenced_column_name "
             f"FROM information_schema.key_column_usage "
             f"WHERE table_schema = {self.quote_string(schema_name)} "
             f"AND table_name = {self.quote_string(table_name)} "