v0.3.0 — Ignore list and result events

Adds an exact entity-ID ignore list to Config Flow and Options Flow. Ignored missing references remain visible under diagnostic ignored_matches but no longer affect sensor state or persistent notifications.

Complete result changes after the baseline scan now fire dashboard_entity_checker_result_changed with previous/current counts, added/removed IDs, full locations, dashboards, and scan time.

Validation: 41 tests, live read-only dashboard precheck, hassfest, HACS validation, and both GitHub workflows passed.