Update the alert digest wording

internal/briefing/alert_digest_module.go

@@ -16,20 +16,24 @@ type AlertDigestModule struct {
 }
 
 type AlertSummary struct {
-	Event    string `json:"event,omitempty"`
-	Headline string `json:"headline,omitempty"`
-	Severity string `json:"severity,omitempty"`
+	Event        string `json:"event,omitempty"`
+	Headline     string `json:"headline,omitempty"`
+	Severity     string `json:"severity,omitempty"`
+	PeriodBegins string `json:"period_begins,omitempty"`
+	PeriodEnds   string `json:"period_ends,omitempty"`
+	Instruction  string `json:"instruction,omitempty"`
+	Description  string `json:"description,omitempty"`
 }
 
 func buildAlertDigestModule(ctx ModuleContext, _ any) (*module.Output, error) {
-	value := alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps)
+	value := alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps, ctx.Timezone)
 	if value == nil {
 		value = &AlertDigestModule{}
 	}
 	return &module.Output{ID: module.AlertDigest, StanzaName: "alert_digest", Value: *value}, nil
 }
 
-func alertDigest(collected facts.CollectedFacts, overlaps []forecast.AlertOverlap) *AlertDigestModule {
+func alertDigest(collected facts.CollectedFacts, overlaps []forecast.AlertOverlap, timezone string) *AlertDigestModule {
 	missing := sourceMissing(collected.SourceProvenance, "alerts")
 	if collected.Alerts == nil && !missing {
 		return nil
@@ -42,9 +46,13 @@ func alertDigest(collected facts.CollectedFacts, overlaps []forecast.AlertOverla
 	value.RelevantCount = len(overlaps)
 	for _, overlap := range overlaps {
 		value.Relevant = append(value.Relevant, AlertSummary{
-			Event:    overlap.Event,
-			Headline: overlap.Headline,
-			Severity: overlap.Severity,
+			Event:        overlap.Event,
+			Headline:     overlap.Headline,
+			Severity:     overlap.Severity,
+			PeriodBegins: friendlyMonthDayTimeLabel(overlap.Period.Start, timezone),
+			PeriodEnds:   friendlyMonthDayTimeLabel(overlap.Period.End, timezone),
+			Instruction:  overlap.Instruction,
+			Description:  overlap.Description,
 		})
 	}
 	return value

internal/briefing/base_modules_test.go

@@ -367,6 +367,39 @@ func TestAlertDigestDistinguishesCheckedEmptyAndMissing(t *testing.T) {
 	}
 }
 
+func TestAlertDigestIncludesPeriodAndGuidance(t *testing.T) {
+	registry := MustDefaultModuleRegistry()
+	ctx := testModuleContext()
+	ctx.Collected.Alerts = &weatherdata.AlertRun{Alerts: []json.RawMessage{json.RawMessage(`{"event":"Wind Advisory"}`)}}
+	ctx.Derived.AlertOverlaps = []forecast.AlertOverlap{{
+		Event:       "Wind Advisory",
+		Headline:    "Wind Advisory until 8 PM",
+		Severity:    "Moderate",
+		Period:      timeutil.Period{Start: mustParseModuleTime("2026-06-17T18:00:00Z"), End: mustParseModuleTime("2026-06-18T01:00:00Z")},
+		Instruction: "Secure outdoor objects.",
+		Description: "Gusty winds may blow around unsecured objects.",
+	}}
+
+	output, err := registry.BuildModule(ctx, module.ConfigItem{ID: module.AlertDigest})
+	if err != nil {
+		t.Fatalf("BuildModule(alert digest) error = %v", err)
+	}
+	value := moduleValue[AlertDigestModule](t, output)
+	if len(value.Relevant) != 1 {
+		t.Fatalf("Relevant length = %d, want 1", len(value.Relevant))
+	}
+	alert := value.Relevant[0]
+	if alert.Event != "Wind Advisory" || alert.Headline != "Wind Advisory until 8 PM" || alert.Severity != "Moderate" {
+		t.Fatalf("alert identity = %#v, want preserved event/headline/severity", alert)
+	}
+	if alert.PeriodBegins != "June 17 at 1:00 PM" || alert.PeriodEnds != "June 17 at 8:00 PM" {
+		t.Fatalf("alert period = %q/%q, want friendly local labels", alert.PeriodBegins, alert.PeriodEnds)
+	}
+	if alert.Instruction != "Secure outdoor objects." || alert.Description != "Gusty winds may blow around unsecured objects." {
+		t.Fatalf("alert guidance = %#v, want instruction and description preserved", alert)
+	}
+}
+
 func TestBaseModulesOmitMissingOptionalOutputs(t *testing.T) {
 	registry := MustDefaultModuleRegistry()
 	ctx := testModuleContext()

internal/briefing/metadata_module.go

@@ -44,7 +44,7 @@ func buildMetadataModule(ctx ModuleContext, _ any) (*module.Output, error) {
 		ValidPeriod:    metadata.ValidPeriod,
 		Location:       copyLocation(ctx.Location),
 		SourceWarnings: sourceWarningSummaries(ctx.Collected.SourceWarnings),
-		Alerts:         alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps),
+		Alerts:         alertDigest(ctx.Collected, ctx.Derived.AlertOverlaps, ctx.Timezone),
 	}
 	return &module.Output{ID: module.Metadata, StanzaName: "metadata", Value: value}, nil
 }

internal/briefing/module_format_helpers.go

@@ -122,6 +122,17 @@ func friendlyDateTimeLabel(value time.Time, timezone string) string {
 	return value.In(location).Format("2006-01-02 at 3:04 PM")
 }
 
+func friendlyMonthDayTimeLabel(value time.Time, timezone string) string {
+	if value.IsZero() {
+		return ""
+	}
+	location, err := timeutil.LoadLocation(timezone)
+	if err != nil {
+		location = time.UTC
+	}
+	return value.In(location).Format("January 2 at 3:04 PM")
+}
+
 func friendlyDateLabel(date string, timezone string) string {
 	location, err := timeutil.LoadLocation(timezone)
 	if err != nil {