Update handlers documentation

**Description**
Currently data lacks proper filtering support.

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

**Priority**: Low/Medium

No file, test, or entry point is named. Start by locating the handlers and tracing how data is currently processed; clarify whether the request is implementation work, documentation work, or both. Done should include configurable filtering with sensible defaults and updated handler documentation.

Scritto dal modello di indicizzazione a partire dal testo della issue.