feat(iace): Phase 1 — Haftungs-Fixes, Massnahmen-Verkabelung, Explainability Engine

Phase 1A — Haftungs-kritische Fixes:
- SIL/PL-Badges als "Vorab-Einschaetzung" mit Tooltip gekennzeichnet
- Coverage-Disclaimer in CE-Akte, Projekt-Uebersicht und Print-Export
- Norm-Referenzen: 42 Kapitelverweise durch Themen-Deskriptoren ersetzt

Phase 1B — Massnahmen-Verkabelung:
- 16 neue Massnahmen (M201-M216) fuer bisher unabgedeckte Kategorien
  (communication_failure, hmi_error, firmware_corruption, maintenance,
  sensor_fault, mode_confusion)
- Kategorie-Fallback im Initialize-Endpoint: ordnet Massnahmen aus der
  Bibliothek automatisch per HazardCategory zu (max 8 pro Kategorie)
- Total: 225 → 241 Massnahmen, 0 Kategorien ohne Massnahmen

Phase 1C — Explainability Engine:
- MatchReason Struct in PatternMatch (type, tag, met)
- Pattern Engine schreibt fuer jeden Match strukturierte Begruendungen
- Frontend zeigt "Erkannt weil: Komponente X, Energie Y, Kein Ausschluss Z"

Weitere Aenderungen:
- BAuA/OSHA Regulatory Hints: 3 Enrich-Endpoints (per Hazard, per Measure, Batch)
- Dokumente-Tab in IACE-Bibliothek (36.708 Chunks aus Qdrant)
- Varianten-UX: Basis-Projekt-Summary auf Varianten-Seite
- Projekt-Initialisierung: POST /initialize kettet Parse→Komponenten→Patterns→Hazards→Massnahmen→Normen
- 18 pre-existing TS-Fehler gefixt, Route-Konflikt behoben
- Component-Library + Measures-Library Tests aktualisiert

Tests: Go alle bestanden, TS 0 Fehler, Playwright 141+ bestanden

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ai-compliance-sdk/internal/api/handlers/iace_handler_documents.go

@@ -0,0 +1,86 @@
+package handlers
+
+import (
+	"net/http"
+	"sort"
+	"strings"
+	"sync"
+
+	"github.com/breakpilot/ai-compliance-sdk/internal/ucca"
+	"github.com/gin-gonic/gin"
+)
+
+// Cached CE corpus document index — built once on first request.
+var (
+	ceCorpusOnce  sync.Once
+	ceCorpusDocs  []ucca.CEDocumentInfo
+	ceCorpusErr   error
+)
+
+// ListCECorpusDocuments returns the deduplicated document index from bp_compliance_ce.
+// GET /iace/ce-corpus-documents
+func (h *IACEHandler) ListCECorpusDocuments(c *gin.Context) {
+	ceCorpusOnce.Do(func() {
+		ceCorpusDocs, ceCorpusErr = h.ragClient.ScrollDocumentIndex(
+			c.Request.Context(), "bp_compliance_ce",
+		)
+		if ceCorpusErr == nil {
+			sort.Slice(ceCorpusDocs, func(i, j int) bool {
+				if ceCorpusDocs[i].Category != ceCorpusDocs[j].Category {
+					return ceCorpusDocs[i].Category < ceCorpusDocs[j].Category
+				}
+				return ceCorpusDocs[i].RegulationID < ceCorpusDocs[j].RegulationID
+			})
+		}
+	})
+
+	if ceCorpusErr != nil {
+		c.JSON(http.StatusInternalServerError, gin.H{
+			"error": "failed to load CE corpus index: " + ceCorpusErr.Error(),
+		})
+		return
+	}
+
+	// Optional search filter
+	query := strings.ToLower(c.Query("q"))
+	category := c.Query("category")
+
+	filtered := ceCorpusDocs
+	if query != "" || category != "" {
+		filtered = make([]ucca.CEDocumentInfo, 0, len(ceCorpusDocs))
+		for _, d := range ceCorpusDocs {
+			if category != "" && d.Category != category {
+				continue
+			}
+			if query != "" {
+				haystack := strings.ToLower(d.RegulationID + " " + d.NameDE + " " + d.NameEN + " " + d.SourceOrg)
+				if !strings.Contains(haystack, query) {
+					continue
+				}
+			}
+			filtered = append(filtered, d)
+		}
+	}
+
+	// Group by category for the response
+	groups := make(map[string][]ucca.CEDocumentInfo)
+	for _, d := range filtered {
+		cat := d.Category
+		if cat == "" {
+			cat = "other"
+		}
+		groups[cat] = append(groups[cat], d)
+	}
+
+	totalChunks := 0
+	for _, d := range filtered {
+		totalChunks += d.ChunkCount
+	}
+
+	c.JSON(http.StatusOK, gin.H{
+		"documents":    filtered,
+		"groups":       groups,
+		"total":        len(filtered),
+		"total_chunks": totalChunks,
+	})
+}