M5-T08: add MQTT, HA Discovery, and Modbus polling config fields

app/config.py

@@ -41,9 +41,21 @@ class Settings(BaseSettings):
     auth_trust_forwarded_for: bool = False
     auth_totp_issuer: str = ""  # defaults to app_name when empty
 
-    # Modbus polling — global kill-switch; T08 will wire this into CONFIG_FIELDS/UI.
+    # Modbus polling — global kill-switch (CONFIG_FIELDS registered in T08).
     modbus_polling_enabled: bool = True
 
+    # MQTT broker connection (T08 wires into CONFIG_FIELDS/UI; T10 builds the client).
+    mqtt_enabled: bool = False
+    mqtt_broker_host: str = ""
+    mqtt_broker_port: int = 1883
+    mqtt_username: str = ""
+    mqtt_password: str = ""
+    mqtt_tls_enabled: bool = False
+
+    # Home Assistant MQTT Discovery (T08 wires into CONFIG_FIELDS/UI; T11 does publishing).
+    ha_discovery_enabled: bool = False
+    ha_discovery_prefix: str = "homeassistant"
+
     model_config = SettingsConfigDict(
         env_file=".env",
         env_file_encoding="utf-8",

app/services/config_page.py

@@ -102,6 +102,25 @@ CONFIG_FIELDS: tuple[ConfigField, ...] = (
         "home_assistant_action_task_project_id",
         "Home Assistant Action Task Project ID",
     ),
+    ConfigField("MQTT", "MQTT_ENABLED", "mqtt_enabled", "MQTT Enabled"),
+    ConfigField("MQTT", "MQTT_BROKER_HOST", "mqtt_broker_host", "MQTT Broker Host"),
+    ConfigField("MQTT", "MQTT_BROKER_PORT", "mqtt_broker_port", "MQTT Broker Port", input_type="number"),
+    ConfigField("MQTT", "MQTT_USERNAME", "mqtt_username", "MQTT Username"),
+    ConfigField("MQTT", "MQTT_PASSWORD", "mqtt_password", "MQTT Password", secret=True),
+    ConfigField("MQTT", "MQTT_TLS_ENABLED", "mqtt_tls_enabled", "MQTT TLS Enabled"),
+    ConfigField(
+        "Home Assistant Discovery",
+        "HA_DISCOVERY_ENABLED",
+        "ha_discovery_enabled",
+        "HA Discovery Enabled",
+    ),
+    ConfigField(
+        "Home Assistant Discovery",
+        "HA_DISCOVERY_PREFIX",
+        "ha_discovery_prefix",
+        "HA Discovery Prefix",
+    ),
+    ConfigField("Modbus", "MODBUS_POLLING_ENABLED", "modbus_polling_enabled", "Modbus Polling Enabled"),
 )
 
 
@@ -292,4 +311,13 @@ def _settings_payload(settings: Settings) -> dict[str, Any]:
         "auth_cookie_secure_override": settings.auth_cookie_secure_override,
         "auth_login_throttle_enabled": settings.auth_login_throttle_enabled,
         "auth_trust_forwarded_for": settings.auth_trust_forwarded_for,
+        "modbus_polling_enabled": settings.modbus_polling_enabled,
+        "mqtt_enabled": settings.mqtt_enabled,
+        "mqtt_broker_host": settings.mqtt_broker_host,
+        "mqtt_broker_port": settings.mqtt_broker_port,
+        "mqtt_username": settings.mqtt_username,
+        "mqtt_password": settings.mqtt_password,
+        "mqtt_tls_enabled": settings.mqtt_tls_enabled,
+        "ha_discovery_enabled": settings.ha_discovery_enabled,
+        "ha_discovery_prefix": settings.ha_discovery_prefix,
     }