Support import configuration

**Description**
Currently middleware lacks proper serialization support.

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

**Priority**: Low/Medium

The issue names no files, tests, or entry points. Start by locating the middleware and import-configuration handling, then determine the intended serialization format and sensible defaults from surrounding project behavior. Done means configurable serialization works for imported middleware without breaking existing behavior, with tests covering the defaults and configuration path.

Written by the indexing model from the issue text.