v2026-02-13.3 — Configurable MQTT Prefix

⚙️ Configurable HA Discovery Prefix (Fixes Issue #12)

• New: mqtt_discovery_prefix setting (Advanced MQTT section). Default is homeassistant.
• Use this if you changed your Home Assistant discovery prefix to something custom (e.g. discover).
• Improved: config.py now prevents empty prefixes, falling back to defaults automatically.

🛠️ Other

• Branches synced.