feat(iace): dual-model risk-suggestion endpoint for Risikobewertung tab

GET /projects/:id/hazards/:hid/risk-suggestion returns BreakPilot's justified
starting values for BOTH risk models per hazard:
- EN-62061-style F/W/P/S (the Excel format the professional knows)
- Fine-Kinney P/E/C (US-recognized)
each with a plain-language justification + the visible formula. Read-only and
computed from public-data anchors (ESAW/NIOSH/OSHA via the engine estimators) —
the professional adjusts the values; no norm table is stored or reproduced.

Adds EstimateFrequency (lifecycle -> 1-5) and BuildRiskSuggestion. Go SDK has no
OpenAPI baseline, so the only contract surface is the frontend consumer (the new
Risikobewertung tab, next).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

ai-compliance-sdk/internal/iace/risk_estimation.go

@@ -166,6 +166,30 @@ func EstimateSeverity(cats []string, scenario string, defaultS int) int {
 	return s
 }
 
+// EstimateFrequency maps the active lifecycle phases to a 1-5 exposure-frequency
+// value for the EN-62061-style model (how often a person is exposed to the
+// task). Our own scale, no norm table.
+func EstimateFrequency(phases []string) int {
+	has := func(n string) bool {
+		for _, p := range phases {
+			if strings.Contains(p, n) {
+				return true
+			}
+		}
+		return false
+	}
+	switch {
+	case has("normal_operation") || has("auto_operation") || has("manual_operation"):
+		return 4
+	case has("setup") || has("maintenance") || has("cleaning") || has("changeover"):
+		return 3
+	case len(phases) > 0:
+		return 2
+	default:
+		return 3
+	}
+}
+
 // EstimateRiskLevel combines the four parameters into BreakPilot's OWN risk
 // index and band. The index is a generic severity-weighted sum of the
 // likelihood factors — index = S * (F + W + P) — i.e. basic arithmetic on the