feat(dsms): Stufe 2+3 — Evidence/TechFile → DSMS + Version Chains + Audit Timeline

Stufe 2A: Evidence Upload → automatische DSMS-Archivierung
- Nach SHA-256 Hash → archive_to_dsms(), CID im Audit-Trail
- Evidence mit CID wird automatisch zu E2 (hash-verifiziert) hochgestuft

Stufe 2B: IACE Tech-File Export → DSMS
- PDF/Excel/DOCX/Markdown Exporte werden nach DSMS archiviert
- archiveTechFile() Helper fuer alle 4 Formate

Stufe 3A: DSMS Gateway — parent_cid + History Endpoint
- parent_cid + tenant_id Felder in DocumentMetadata
- GET /documents/{cid}/history — folgt parent_cid-Chain (max 50 deep)

Stufe 3C: Audit Timeline UI
- Neue Seite /sdk/audit-timeline
- Vertikale Timeline mit farbigen Action-Dots
- Filter: Alle, Nachweis, DSMS-Archiv, Control, Dokument, DSFA, VVT, TOM
- CID-Badges fuer DSMS-archivierte Eintraege

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

admin-compliance/app/sdk/audit-timeline/_hooks/useAuditTimeline.ts

@@ -0,0 +1,46 @@
+'use client'
+
+import { useState, useEffect } from 'react'
+
+export interface AuditEntry {
+  id: string
+  entity_type: string
+  entity_id: string
+  entity_name: string
+  action: string
+  field_changed: string | null
+  old_value: string | null
+  new_value: string | null
+  change_summary: string | null
+  performed_by: string
+  performed_at: string
+}
+
+export function useAuditTimeline() {
+  const [entries, setEntries] = useState<AuditEntry[]>([])
+  const [loading, setLoading] = useState(true)
+  const [filter, setFilter] = useState<string>('all')
+
+  useEffect(() => {
+    loadEntries()
+  }, [filter]) // eslint-disable-line react-hooks/exhaustive-deps
+
+  async function loadEntries() {
+    setLoading(true)
+    try {
+      const params = new URLSearchParams({ limit: '100' })
+      if (filter !== 'all') params.set('entity_type', filter)
+      const res = await fetch(`/api/sdk/v1/compliance/audit-trail?${params}`)
+      if (res.ok) {
+        const json = await res.json()
+        setEntries(json.entries || json.audit_trail || json || [])
+      }
+    } catch (err) {
+      console.error('Failed to load audit trail:', err)
+    } finally {
+      setLoading(false)
+    }
+  }
+
+  return { entries, loading, filter, setFilter }
+}