Add rate limiting for import

**Description**
Currently parsers lacks proper backup support.

**Proposed solution**
Add configurable backup with sensible defaults.

**Priority**: Low/Medium

First reconcile the title's rate-limiting request with the body, which asks for configurable parser backup support. Locate the parser/import entry point and any existing backup configuration or tests; the issue names no files. Done should include an agreed scope, sensible defaults, and verification that the requested import behavior works without breaking existing parsing.

Written by the indexing model from the issue text.