Release 1.2.0: Radio-Aware Monitoring and Smarter Updates

[yellowcooln]

Summary

Prepare openHop Repeater Home Assistant integration 1.2.0 by promoting dev to main.

• Add radio child devices, explicit identity aliases, reversible retirement/restoration, and single-fabric support while preserving existing names and registry identities
• Add aggregate radio health, traffic counters, plugin diagnostics, sensor freshness, and battery charge trends
• Add native software update controls and hourly checks at HH:01, respecting backend cache/backoff and keeping branch discovery out of automatic polling
• Expand MQTT, advert, and neighbor-history controls; correct advanced-action HTTP budgets and expose optional companion status/telemetry responses and explicit send failures
• Refresh native dashboards, add seven opt-in alert blueprints, expand diagnostics redaction, and update documentation and the 1.2.0 changelog

Compatibility

• Preserve the pymc_repeater integration/service domain and established entity identifiers
• Backend radio ID changes require an operator-confirmed alias; permanent device removal does not preserve registry identity
• Per-reading sensor cadence is consumed when supplied by the backend. The separate backend metadata patch is not included here; older backends retain the global-summary fallback

Verification

• 103 local tests passed, plus compilation, JSON/YAML validation, and whitespace checks
• Python Smoke, HACS, and Hassfest passed on head commit da90d43
• Live HA deployment verified startup completion, three loaded integration entries, new radio-health entities, preserved existing reporting entities and radio identity, optional service-response metadata, and dashboard save/read-back
• No openHop integration errors observed after restart
• Tests use source/fake boundaries; advanced RF actions and actual hourly scheduler dispatch have not been exhaustively verified live

Draft for release review only; no merge or release publication requested.