Add configuration options for retry

**Description**
Currently handlers lacks proper retry support.

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

**Priority**: Low/Medium

No files, tests, or handler entry points are named. Start by locating the handler implementation and existing configuration path, then define sensible retry defaults and configuration behavior; done means handlers retry correctly under the supported settings and the behavior is covered by tests.

Written by the indexing model from the issue text.