v0.9.0 — Connection diagnostics

New

• Connection sub-device groups all link-level diagnostics (Adapter, RSSI, Last Seen, BLE Connected) under a dedicated device. ESP Bridge entities (Bridge Version, Alive) also move here.
• Adapter sensor shows which scanner/proxy/ESP currently carries the connection — same name as in Settings → Bluetooth. Helps diagnosing proxy-flapping in multi-proxy households.
• BLE Connected is now also exposed for Direct BLE (previously ESP Bridge only).
• Config-flow capabilities dialog shows the connect path at the top.
• Every connect logs the adapter path for correlation with the HA Bluetooth page.

Also included (previously unreleased)

• bluetooth_proxy coexistence workaround: pre-build patch (esphome/bluedroid_null_fix.py) cherry-picks NULL-pointer checks from ESP-IDF d4f3517 to prevent a bta_gattc_cache_save LoadProhibited crash when bluetooth_proxy runs alongside ble_client on the same ESP32. Tracking: esphome/esphome#15783.
• HX6322 and HX6352 (For Kids) added to the compatibility list.

Migration

No action required. Entity IDs and unique_ids are unchanged, the existing _bridge device is reused as the Connection device. ESP Bridge users see the sub-device renamed to "Connection" on restart; custom names/area assignments are preserved. Direct BLE users gain the new Connection sub-device; RSSI and Last Seen move there (entity IDs stay).