Extends ImportDialog to handle .sql dump files alongside CSV/JSON. Adds _SqlImportWorker that splits SQL with sqlparse (semicolon fallback), executes each statement via driver.execute_query(), and collects non-fatal errors. UI shows a text preview of the dump, statement count, a stop-on-error checkbox, and a final summary with any per-statement errors. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>