feat: make home assistant add-on run optimization by default (#940)

When running as Home Assistant add-on the only viable usage is running with
cyclic optimization. Make this the default to als propvide a better experience
for first time users. The optimization will start with demo data, which also
helps to configure Akkudoktor-EOS to the personal usage.

The disabling of the automatic energy management is now an explicit mode
"DISABLED".

Signed-off-by: Bobby Noelte <b0661n0e17e@gmail.com>

src/akkudoktoreos/core/emsettings.py

@@ -4,19 +4,47 @@ Kept in an extra module to avoid cyclic dependencies on package import.
 """
 
 from enum import Enum
-from typing import Optional
+from typing import Optional, Union
 
 from pydantic import Field
 
-from akkudoktoreos.config.configabc import SettingsBaseModel
+from akkudoktoreos.config.configabc import SettingsBaseModel, is_home_assistant_addon
 
 
 class EnergyManagementMode(str, Enum):
     """Energy management mode."""
 
+    DISABLED = "DISABLED"
     PREDICTION = "PREDICTION"
     OPTIMIZATION = "OPTIMIZATION"
 
+    @classmethod
+    def is_valid(cls, mode: Union[str, "EnergyManagementMode"]) -> bool:
+        """Check if value is a valid mode."""
+        try:
+            cls(mode)
+            return True
+        except (ValueError, TypeError):
+            return False
+
+    @classmethod
+    def from_value(cls, value: str) -> Optional["EnergyManagementMode"]:
+        """Safely convert string to enum, return None if invalid."""
+        try:
+            return cls(value)
+        except ValueError:
+            return None
+
+
+def ems_default_mode() -> EnergyManagementMode:
+    """Provide default EMS mode.
+
+    Returns OPTIMIZATION when running under Home Assistant, else DISABLED.
+    """
+    if is_home_assistant_addon():
+        return EnergyManagementMode.OPTIMIZATION
+    return EnergyManagementMode.DISABLED
+
 
 class EnergyManagementCommonSettings(SettingsBaseModel):
     """Energy Management Configuration."""
@@ -38,10 +66,10 @@ class EnergyManagementCommonSettings(SettingsBaseModel):
         },
     )
 
-    mode: Optional[EnergyManagementMode] = Field(
-        default=None,
+    mode: EnergyManagementMode = Field(
+        default_factory=ems_default_mode,
         json_schema_extra={
-            "description": "Energy management mode [OPTIMIZATION | PREDICTION].",
+            "description": "Energy management mode [DISABLED | OPTIMIZATION | PREDICTION].",
             "examples": ["OPTIMIZATION", "PREDICTION"],
         },
     )