fix(core): Oracle 复制 INSERT 按行生成语句

* fix(core): emit oracle copy inserts per row

* refactor(core): extract single-row insert dialect check into sql_dialect

---------

Co-authored-by: zero <zero@zeroMacmini.local>
Co-authored-by: t8y2 <1156263951@qq.com>

crates/dbx-core/src/sql_dialect.rs

@@ -8,7 +8,7 @@ mod tests;
 
 pub use capabilities::{
     firebird_rows_clause, is_schema_aware, pagination_strategy, table_pagination_strategy, uses_fetch_first,
-    PaginationContext, TablePaginationStrategy,
+    uses_single_row_insert_statements, PaginationContext, TablePaginationStrategy,
 };
 pub use identifiers::{normalize_where_input, qualified_table_name, quote_table_identifier};
 pub(crate) use identifiers::{parse_sqlserver_linked_schema_ref, qualified_transfer_table, quote_transfer_identifier};