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/app/api/sdk/v1/projects/[projectId]/route.ts

@@ -0,0 +1,120 @@
+import { NextRequest, NextResponse } from 'next/server'
+
+const BACKEND_URL = process.env.BACKEND_URL || 'http://backend-compliance:8002'
+
+/**
+ * Proxy: GET /api/sdk/v1/projects/{projectId} → Backend
+ */
+export async function GET(
+  request: NextRequest,
+  { params }: { params: Promise<{ projectId: string }> }
+) {
+  try {
+    const { projectId } = await params
+    const tenantId = request.headers.get('X-Tenant-ID') ||
+      new URL(request.url).searchParams.get('tenant_id') || ''
+
+    const response = await fetch(
+      `${BACKEND_URL}/api/v1/projects/${projectId}?tenant_id=${encodeURIComponent(tenantId)}`,
+      {
+        headers: { 'X-Tenant-ID': tenantId },
+      }
+    )
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      return NextResponse.json(
+        { error: 'Backend error', details: errorText },
+        { status: response.status }
+      )
+    }
+
+    return NextResponse.json(await response.json())
+  } catch (error) {
+    console.error('Failed to get project:', error)
+    return NextResponse.json(
+      { error: 'Failed to connect to backend' },
+      { status: 503 }
+    )
+  }
+}
+
+/**
+ * Proxy: PATCH /api/sdk/v1/projects/{projectId} → Backend
+ */
+export async function PATCH(
+  request: NextRequest,
+  { params }: { params: Promise<{ projectId: string }> }
+) {
+  try {
+    const { projectId } = await params
+    const body = await request.json()
+    const tenantId = body.tenant_id || request.headers.get('X-Tenant-ID') || ''
+
+    const response = await fetch(
+      `${BACKEND_URL}/api/v1/projects/${projectId}?tenant_id=${encodeURIComponent(tenantId)}`,
+      {
+        method: 'PATCH',
+        headers: {
+          'Content-Type': 'application/json',
+          'X-Tenant-ID': tenantId,
+        },
+        body: JSON.stringify(body),
+      }
+    )
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      return NextResponse.json(
+        { error: 'Backend error', details: errorText },
+        { status: response.status }
+      )
+    }
+
+    return NextResponse.json(await response.json())
+  } catch (error) {
+    console.error('Failed to update project:', error)
+    return NextResponse.json(
+      { error: 'Failed to connect to backend' },
+      { status: 503 }
+    )
+  }
+}
+
+/**
+ * Proxy: DELETE /api/sdk/v1/projects/{projectId} → Backend (soft delete)
+ */
+export async function DELETE(
+  request: NextRequest,
+  { params }: { params: Promise<{ projectId: string }> }
+) {
+  try {
+    const { projectId } = await params
+    const tenantId = request.headers.get('X-Tenant-ID') ||
+      new URL(request.url).searchParams.get('tenant_id') || ''
+
+    const response = await fetch(
+      `${BACKEND_URL}/api/v1/projects/${projectId}?tenant_id=${encodeURIComponent(tenantId)}`,
+      {
+        method: 'DELETE',
+        headers: { 'X-Tenant-ID': tenantId },
+      }
+    )
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      return NextResponse.json(
+        { error: 'Backend error', details: errorText },
+        { status: response.status }
+      )
+    }
+
+    return NextResponse.json(await response.json())
+  } catch (error) {
+    console.error('Failed to archive project:', error)
+    return NextResponse.json(
+      { error: 'Failed to connect to backend' },
+      { status: 503 }
+    )
+  }
+}

admin-compliance/app/api/sdk/v1/projects/route.ts

@@ -0,0 +1,75 @@
+import { NextRequest, NextResponse } from 'next/server'
+
+const BACKEND_URL = process.env.BACKEND_URL || 'http://backend-compliance:8002'
+
+/**
+ * Proxy: GET /api/sdk/v1/projects → Backend GET /api/v1/projects
+ */
+export async function GET(request: NextRequest) {
+  try {
+    const { searchParams } = new URL(request.url)
+    const tenantId = searchParams.get('tenant_id') || request.headers.get('X-Tenant-ID') || ''
+    const includeArchived = searchParams.get('include_archived') || 'false'
+
+    const response = await fetch(
+      `${BACKEND_URL}/api/v1/projects?tenant_id=${encodeURIComponent(tenantId)}&include_archived=${includeArchived}`,
+      {
+        headers: { 'X-Tenant-ID': tenantId },
+      }
+    )
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      return NextResponse.json(
+        { error: 'Backend error', details: errorText },
+        { status: response.status }
+      )
+    }
+
+    return NextResponse.json(await response.json())
+  } catch (error) {
+    console.error('Failed to list projects:', error)
+    return NextResponse.json(
+      { error: 'Failed to connect to backend' },
+      { status: 503 }
+    )
+  }
+}
+
+/**
+ * Proxy: POST /api/sdk/v1/projects → Backend POST /api/v1/projects
+ */
+export async function POST(request: NextRequest) {
+  try {
+    const body = await request.json()
+    const tenantId = body.tenant_id || request.headers.get('X-Tenant-ID') || ''
+
+    const response = await fetch(
+      `${BACKEND_URL}/api/v1/projects?tenant_id=${encodeURIComponent(tenantId)}`,
+      {
+        method: 'POST',
+        headers: {
+          'Content-Type': 'application/json',
+          'X-Tenant-ID': tenantId,
+        },
+        body: JSON.stringify(body),
+      }
+    )
+
+    if (!response.ok) {
+      const errorText = await response.text()
+      return NextResponse.json(
+        { error: 'Backend error', details: errorText },
+        { status: response.status }
+      )
+    }
+
+    return NextResponse.json(await response.json(), { status: 201 })
+  } catch (error) {
+    console.error('Failed to create project:', error)
+    return NextResponse.json(
+      { error: 'Failed to connect to backend' },
+      { status: 503 }
+    )
+  }
+}