fix: enforce SCADA chart device coverage

app/domain/schemas/operational_task.py

@@ -320,6 +320,7 @@ class InvestigationReport(StrictModel):
     data_gaps: list[InvestigationDataGap] | None = None
     diagram: InvestigationDiagram | None = None
     ui_blocks: list["ReportUiBlock"] = Field(default_factory=list, max_length=8)
+    scada_device_ids: list[TaskFeatureId] | None = Field(default=None, max_length=1000)
 
     @model_validator(mode="after")
     def validate_result(self):
@@ -742,8 +743,27 @@ class AgentArtifactsResult(StrictModel):
     progress_revision: PositiveInt | None = None
 
 
+class ScadaChartGap(StrictModel):
+    device_id: TaskFeatureId
+    day_offset: Annotated[int, Field(ge=0, le=7)]
+    missing_count: Annotated[int, Field(ge=1, le=100)]
+    reason: Literal["no_readings", "outside_frozen_scope", "outside_frozen_window", "no_scheduled_samples"]
+
+
+class ScadaChartContext(StrictModel):
+    role: Literal["current", "comparison"]
+    metric: Literal["pressure", "flow"]
+    unit: Annotated[str, Field(min_length=1, max_length=128)]
+    window_start: WorkbenchDateTime
+    window_end: WorkbenchDateTime
+    value_field: Literal["monitored_value", "cleaned_value"] = "monitored_value"
+    gaps: list[ScadaChartGap] = Field(default_factory=list, max_length=8)
+
+
 class TaskSafeChartSeries(StrictModel):
     name: Annotated[str, Field(max_length=128)]
+    device_id: TaskFeatureId | None = None
+    day_offset: Annotated[int, Field(ge=0, le=7)] | None = None
     type: Literal["line", "bar", "scatter"] | None = None
     data: Annotated[list[Annotated[float, Field(strict=True, allow_inf_nan=False)] | None], Field(min_length=1, max_length=100)]
     sample_times: Annotated[list[Annotated[str, Field(
@@ -770,6 +790,7 @@ class TaskSafeChartSeries(StrictModel):
 
 class TaskSafeChart(StrictModel):
     title: Annotated[str, Field(max_length=200)]
+    scada: ScadaChartContext | None = None
     chart_type: Literal["line", "bar", "time_comparison"]
     x_axis_name: Annotated[str, Field(max_length=128)] | None = None
     y_axis_name: Annotated[str, Field(max_length=128)] | None = None