feat(iace): secondary-harm chain model + AllPatterns drift fix

Task #17 — Folgegefahren-Modell as Vorbereitungs-Commit (no DB schema
change yet; persistence via separate [migration-approved] commit).

New:
- secondary_harms.go: SecondaryHarm struct + six canonical categories
  (consumer_safety, product_liability, food_safety, environmental,
  reputation, financial) with DE labels.
- hazard_pattern_types.go: HazardPattern extended with optional
  SecondaryHarms field — pattern library can now attach consequential-
  damage chains.
- hazard_patterns_secondary_demo.go: two worked examples
  - HP2000 Glasbruch carbonated bottling (the "Cola splitter" scenario
    from the IACE strategy discussion) with consumer_safety + food_safety
    + reputation chains
  - HP2001 Pharma fill-finish cross-contamination with consumer_safety
    + product_liability under AMG §84

Bonus fix:
- compliance_crossover.go AllPatterns() was a duplicate enumeration that
  silently drifted from collectAllPatterns() in pattern_registry.go.
  Pre-fix: 1058 patterns visible. Post-fix: 1213 patterns. The 155 invisible
  patterns included CRA, ISO12100 gaps, robot-cell, CNC extended, VDMA,
  textile-agri, GT-bremse — anything added after the original AllPatterns
  was authored. Audit-Suite (cmd/iace-audit) now sees the full set.

Next steps for full secondary-harm rollout:
- DB migration: hazards table + secondary_harms array column
- API: surface secondary_harms in /projects/:id/hazards response
- Frontend: collapsible Folgegefahren-Panel in HazardTable

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

@@ -42,5 +42,6 @@ func collectAllPatterns() []HazardPattern {
 	patterns = append(patterns, GetGTBremseHazardPatterns()...)       // HP1710-HP1729 GT Bremse coverage gaps
 	patterns = append(patterns, GetISO12100GapPatterns()...)          // HP1900-HP1909 ISO 12100 Annex B gaps (Vakuum, Federn, Rutsch, Hochdruckinjektion, Ersticken)
 	patterns = append(patterns, GetCRAPatterns()...)                  // HP1910-HP1918 CRA / DIN EN 40000-1-2 cyber-resilience spur
+	patterns = append(patterns, GetSecondaryHarmDemoPatterns()...)    // HP2000-HP2001 secondary harm chain demos (Cola splitter, Pharma)
 	return patterns
 }