Restore column-name casing in Turso error messages

Turso lowercases column names in UNIQUE-constraint error messages
("_tmp_table.id" vs SQLite's "_tmp_table.ID"). Extend the existing
error-normalizer callback to look up the canonical casing from
information_schema.columns and substitute it back.

Fixes testAlterTableModifyColumnComplexChange.

Author: JanJakes

.github/workflows/phpunit-tests-turso.yml

@@ -914,6 +914,27 @@ jobs:
               "\t\t\t\t},\n"
               "\t\t\t\t$msg\n"
               "\t\t\t);\n"
+              "\t\t\t// Turso lowercases column names in UNIQUE-constraint errors;\n"
+              "\t\t\t// restore original casing from information_schema.\n"
+              "\t\t\t$msg = preg_replace_callback(\n"
+              "\t\t\t\t'/(\\w+)\\.(\\w+)/',\n"
+              "\t\t\t\tfunction ( $m ) {\n"
+              "\t\t\t\t\ttry {\n"
+              "\t\t\t\t\t\t$cols_table = $this->information_schema_builder->get_table_name( false, 'columns' );\n"
+              "\t\t\t\t\t\t$canonical = $this->execute_sqlite_query(\n"
+              "\t\t\t\t\t\t\tsprintf(\n"
+              "\t\t\t\t\t\t\t\t'SELECT column_name FROM %s WHERE table_name = ? AND lower(column_name) = ?',\n"
+              "\t\t\t\t\t\t\t\t$this->quote_sqlite_identifier( $cols_table )\n"
+              "\t\t\t\t\t\t\t),\n"
+              "\t\t\t\t\t\t\tarray( $m[1], strtolower( $m[2] ) )\n"
+              "\t\t\t\t\t\t)->fetchColumn();\n"
+              "\t\t\t\t\t\treturn $m[1] . '.' . ( $canonical !== false ? $canonical : $m[2] );\n"
+              "\t\t\t\t\t} catch ( \\Throwable $_ ) {\n"
+              "\t\t\t\t\t\treturn $m[0];\n"
+              "\t\t\t\t\t}\n"
+              "\t\t\t\t},\n"
+              "\t\t\t\t$msg\n"
+              "\t\t\t);\n"
               "\t\t\tthrow $this->new_driver_exception( $msg, $e->getCode(), $e );"
           )
           assert old in src, 'rethrow block not found'