v0.28.0 — Charge Assistant: handback default, EM340 parity, reminder + efficiency

Rolls up 0.24.0 → 0.28.0.

Charge Assistant — return-to-default on control release

• New "return the charger to a default when the Assistant/Add-on stops controlling" option — for when a mode is turned off or a stray/leftover start leaves it charging with nothing watching it. Defaults to Resume Eco-Smart / Solar: hands the charger back to its own schedule + solar rather than leaving it paused/idle. Only ever acts on charges the integration/add-on owned — manual and native-schedule charges are never touched. Degrades gracefully on chargers without solar. Validated end-to-end on hardware.

Per-phase EM340 / Power-Boost meter

• Added Mains Voltage L2/L3 and House Current L2/L3 sensors, at parity with MQTT discovery (community contribution, thanks @hannesjanno).
• Fixed: House Current read ~10× too high — the meter's per-phase current is in deci-amps; it's now scaled correctly (16 A reads 16.0 A, not 160 A).

Plug-in reminders

• Fixed reminder spam: a flappy presence entity (phone GPS/Wi-Fi bouncing home→away→home) fired a fresh notification each time. A 30-minute cooldown now gates repeats (the escalation re-nudge is unaffected; it resets when the car plugs in).

Smart-charge commute efficiency

• Self-learning efficiency (kWh/100km): the odometer source can now learn your real consumption from SOC-drop × battery over the odometer distance (Auto, default when odometer + SOC + battery are set), read a Sensor, or use a Fixed value. No more hand-entered guess.

Full detail in CHANGELOG.md.