feat(sdk): Multi-Projekt-Architektur — mehrere Projekte pro Tenant

Jeder Tenant kann jetzt mehrere Compliance-Projekte anlegen (z.B. verschiedene
Produkte, Tochterunternehmen). CompanyProfile ist pro Projekt kopierbar und
danach unabhaengig editierbar. Multi-Tab-Support via separater BroadcastChannel
und localStorage Keys pro Projekt.

- Migration 039: compliance_projects Tabelle, sdk_states.project_id
- Backend: FastAPI CRUD-Routes fuer Projekte mit Tenant-Isolation
- Frontend: ProjectSelector UI, SDKProvider mit projectId, URL ?project=
- State API: UPSERT auf (tenant_id, project_id) mit Abwaertskompatibilitaet
- Tests: pytest fuer Model-Validierung, Row-Konvertierung, Tenant-Isolation
- Docs: MKDocs Seite, CLAUDE.md, Backend README

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

admin-compliance/lib/sdk/context.tsx

@@ -16,6 +16,7 @@ import {
   ImportedDocument,
   GapAnalysis,
   SDKPackageId,
+  ProjectInfo,
   SDK_STEPS,
   SDK_PACKAGES,
   getStepById,
@@ -57,6 +58,10 @@ const initialState: SDKState = {
   userId: '',
   subscription: 'PROFESSIONAL',
 
+  // Project Context
+  projectId: '',
+  projectInfo: null,
+
   // Customer Type
   customerType: null,
 
@@ -548,6 +553,13 @@ interface SDKContextValue {
   // Command Bar
   isCommandBarOpen: boolean
   setCommandBarOpen: (open: boolean) => void
+
+  // Project Management
+  projectId: string | undefined
+  createProject: (name: string, customerType: CustomerType, copyFromProjectId?: string) => Promise<ProjectInfo>
+  listProjects: () => Promise<ProjectInfo[]>
+  switchProject: (projectId: string) => void
+  archiveProject: (projectId: string) => Promise<void>
 }
 
 const SDKContext = createContext<SDKContextValue | null>(null)
@@ -562,6 +574,7 @@ interface SDKProviderProps {
   children: React.ReactNode
   tenantId?: string
   userId?: string
+  projectId?: string
   enableBackendSync?: boolean
 }
 
@@ -569,6 +582,7 @@ export function SDKProvider({
   children,
   tenantId = 'default',
   userId = 'default',
+  projectId,
   enableBackendSync = false,
 }: SDKProviderProps) {
   const router = useRouter()
@@ -577,6 +591,7 @@ export function SDKProvider({
     ...initialState,
     tenantId,
     userId,
+    projectId: projectId || '',
   })
   const [isCommandBarOpen, setCommandBarOpen] = React.useState(false)
   const [isInitialized, setIsInitialized] = React.useState(false)
@@ -597,7 +612,7 @@ export function SDKProvider({
   // Initialize API client and sync manager
   useEffect(() => {
     if (enableBackendSync && typeof window !== 'undefined') {
-      apiClientRef.current = getSDKApiClient(tenantId)
+      apiClientRef.current = getSDKApiClient(tenantId, projectId)
 
       syncManagerRef.current = createStateSyncManager(
         apiClientRef.current,
@@ -640,7 +655,8 @@ export function SDKProvider({
             setIsOnline(true)
             setSyncState(prev => ({ ...prev, status: 'idle' }))
           },
-        }
+        },
+        projectId
       )
     }
 
@@ -654,7 +670,7 @@ export function SDKProvider({
         apiClientRef.current = null
       }
     }
-  }, [enableBackendSync, tenantId])
+  }, [enableBackendSync, tenantId, projectId])
 
   // Sync current step with URL
   useEffect(() => {
@@ -666,12 +682,17 @@ export function SDKProvider({
     }
   }, [pathname, state.currentStep])
 
+  // Storage key — per tenant+project
+  const storageKey = projectId
+    ? `${SDK_STORAGE_KEY}-${tenantId}-${projectId}`
+    : `${SDK_STORAGE_KEY}-${tenantId}`
+
   // Load state on mount (localStorage first, then server)
   useEffect(() => {
     const loadInitialState = async () => {
       try {
         // First, try loading from localStorage
-        const stored = localStorage.getItem(`${SDK_STORAGE_KEY}-${tenantId}`)
+        const stored = localStorage.getItem(storageKey)
         if (stored) {
           const parsed = JSON.parse(stored)
           if (parsed.lastModified) {
@@ -699,7 +720,7 @@ export function SDKProvider({
     }
 
     loadInitialState()
-  }, [tenantId, enableBackendSync])
+  }, [tenantId, projectId, enableBackendSync, storageKey])
 
   // Auto-save to localStorage and sync to server
   useEffect(() => {
@@ -707,8 +728,8 @@ export function SDKProvider({
 
     const saveTimeout = setTimeout(() => {
       try {
-        // Save to localStorage
-        localStorage.setItem(`${SDK_STORAGE_KEY}-${tenantId}`, JSON.stringify(state))
+        // Save to localStorage (per tenant+project)
+        localStorage.setItem(storageKey, JSON.stringify(state))
 
         // Sync to server if backend sync is enabled
         if (enableBackendSync && syncManagerRef.current) {
@@ -720,7 +741,7 @@ export function SDKProvider({
     }, 1000)
 
     return () => clearTimeout(saveTimeout)
-  }, [state, tenantId, isInitialized, enableBackendSync])
+  }, [state, tenantId, projectId, isInitialized, enableBackendSync, storageKey])
 
   // Keyboard shortcut for Command Bar
   useEffect(() => {
@@ -746,10 +767,11 @@ export function SDKProvider({
       const step = getStepById(stepId)
       if (step) {
         dispatch({ type: 'SET_CURRENT_STEP', payload: stepId })
-        router.push(step.url)
+        const url = projectId ? `${step.url}?project=${projectId}` : step.url
+        router.push(url)
       }
     },
-    [router]
+    [router, projectId]
   )
 
   const goToNextStep = useCallback(() => {
@@ -992,7 +1014,7 @@ export function SDKProvider({
       }
 
       // Also save to localStorage for immediate availability
-      localStorage.setItem(`${SDK_STORAGE_KEY}-${tenantId}`, JSON.stringify(demoState))
+      localStorage.setItem(storageKey, JSON.stringify(demoState))
 
       // Update local state
       dispatch({ type: 'LOAD_DEMO_DATA', payload: demoState })
@@ -1005,7 +1027,7 @@ export function SDKProvider({
         message: error instanceof Error ? error.message : 'Unbekannter Fehler beim Laden der Demo-Daten',
       }
     }
-  }, [tenantId, userId, enableBackendSync])
+  }, [tenantId, userId, enableBackendSync, storageKey])
 
   // Clear demo data
   const clearDemoData = useCallback(async (): Promise<boolean> => {
@@ -1016,7 +1038,7 @@ export function SDKProvider({
       }
 
       // Clear localStorage
-      localStorage.removeItem(`${SDK_STORAGE_KEY}-${tenantId}`)
+      localStorage.removeItem(storageKey)
 
       // Reset local state
       dispatch({ type: 'RESET_STATE' })
@@ -1026,7 +1048,7 @@ export function SDKProvider({
       console.error('Failed to clear demo data:', error)
       return false
     }
-  }, [tenantId, enableBackendSync])
+  }, [storageKey, enableBackendSync])
 
   // Check if demo data is loaded (has use cases with demo- prefix)
   const isDemoDataLoaded = useMemo(() => {
@@ -1036,7 +1058,7 @@ export function SDKProvider({
   // Persistence
   const saveState = useCallback(async (): Promise<void> => {
     try {
-      localStorage.setItem(`${SDK_STORAGE_KEY}-${tenantId}`, JSON.stringify(state))
+      localStorage.setItem(storageKey, JSON.stringify(state))
 
       if (enableBackendSync && syncManagerRef.current) {
         await syncManagerRef.current.forcSync(state)
@@ -1045,7 +1067,7 @@ export function SDKProvider({
       console.error('Failed to save SDK state:', error)
       throw error
     }
-  }, [state, tenantId, enableBackendSync])
+  }, [state, storageKey, enableBackendSync])
 
   const loadState = useCallback(async (): Promise<void> => {
     try {
@@ -1058,7 +1080,7 @@ export function SDKProvider({
       }
 
       // Fall back to localStorage
-      const stored = localStorage.getItem(`${SDK_STORAGE_KEY}-${tenantId}`)
+      const stored = localStorage.getItem(storageKey)
       if (stored) {
         const parsed = JSON.parse(stored)
         dispatch({ type: 'SET_STATE', payload: parsed })
@@ -1067,7 +1089,7 @@ export function SDKProvider({
       console.error('Failed to load SDK state:', error)
       throw error
     }
-  }, [tenantId, enableBackendSync])
+  }, [storageKey, enableBackendSync])
 
   // Force sync to server
   const forceSyncToServer = useCallback(async (): Promise<void> => {
@@ -1076,6 +1098,49 @@ export function SDKProvider({
     }
   }, [state, enableBackendSync])
 
+  // Project Management
+  const createProject = useCallback(
+    async (name: string, customerType: CustomerType, copyFromProjectId?: string): Promise<ProjectInfo> => {
+      if (!apiClientRef.current) {
+        throw new Error('Backend sync not enabled')
+      }
+      return apiClientRef.current.createProject({
+        name,
+        customer_type: customerType,
+        copy_from_project_id: copyFromProjectId,
+      })
+    },
+    []
+  )
+
+  const listProjectsFn = useCallback(async (): Promise<ProjectInfo[]> => {
+    if (!apiClientRef.current) {
+      return []
+    }
+    const result = await apiClientRef.current.listProjects()
+    return result.projects
+  }, [])
+
+  const switchProject = useCallback(
+    (newProjectId: string) => {
+      // Navigate to the SDK dashboard with the new project
+      const params = new URLSearchParams(window.location.search)
+      params.set('project', newProjectId)
+      router.push(`/sdk?${params.toString()}`)
+    },
+    [router]
+  )
+
+  const archiveProjectFn = useCallback(
+    async (archiveId: string): Promise<void> => {
+      if (!apiClientRef.current) {
+        throw new Error('Backend sync not enabled')
+      }
+      await apiClientRef.current.archiveProject(archiveId)
+    },
+    []
+  )
+
   // Export
   const exportState = useCallback(
     async (format: 'json' | 'pdf' | 'zip'): Promise<Blob> => {
@@ -1136,6 +1201,11 @@ export function SDKProvider({
     exportState,
     isCommandBarOpen,
     setCommandBarOpen,
+    projectId,
+    createProject,
+    listProjects: listProjectsFn,
+    switchProject,
+    archiveProject: archiveProjectFn,
   }
 
   return <SDKContext.Provider value={value}>{children}</SDKContext.Provider>