Pentest 55.2 + 55.3 HIGH + 55.4 + 53.3: Notes/Document-Auth/Race/Generate

55.3 HIGH (Contract-Documents ohne Auth abrufbar):
- /uploads/contract-documents/*.pdf war HTTP 200 ohne Token, weil
  nginx die Datei direkt ausliefert und Backend nur /api/uploads/*
  schützte.
- Defense-in-Depth: app.get('/uploads/*') jetzt ebenfalls mit
  authenticate + downloadFile (Ownership-Check) abgesichert.
  Falls nginx fehlkonfiguriert sein sollte, fängt das Backend.

55.2 MEDIUM (notes ungestrippt + unlimitiert):
- Neuer sanitizeNotes-Helper: stripHtml + CRLF→LF + Control-Chars
  raus + Cap 2000 Zeichen. Eingesetzt für ContractDocument.notes
  in allen 3 Schreibpfaden (contract.controller, saveAttachment-
  AsContractDocument, saveEmailAsContractDocument).
- documentType zusätzlich stripHtml.

55.4 LOW (Race: 5x Lieferbestätigung → 5 Dokumente):
- Neuer In-Memory-Lock per (contractId, documentType) in
  contractStatusScheduler.service. withContractDocumentLock führt
  Recent-Duplicate-Check (10s-Window) + Write atomar aus.
- In cachedEmail-Pfaden: fs.writeFileSync ist jetzt INNERHALB des
  Locks → kein verwaister Datei-Müll bei Race-Reject.

53.3 (Prisma-Client veraltet bei ungebauten Images):
- docker-entrypoint.sh: `prisma generate` am Container-Start
  hinzugefügt. Kostet ~5–10 s, regeneriert den Client gegen das
  aktuelle Schema falls jemand ein Stale-Image hochgezogen hat.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

backend/src/controllers/cachedEmail.controller.ts

@@ -8,11 +8,12 @@ import { sendEmail, SmtpCredentials, SendEmailParams, EmailAttachment } from '..
 import { fetchAttachment, appendToSent, ImapCredentials } from '../services/imapService.js';
 import { getImapSmtpSettings } from '../services/emailProvider/emailProviderService.js';
 import { decrypt } from '../utils/encryption.js';
+import { sanitizeNotes, stripHtml } from '../utils/sanitize.js';
 import { logChange } from '../services/audit.service.js';
 import { ApiResponse, AuthRequest } from '../types/index.js';
 import { getCustomerTargets, getContractTargets, getIdentityDocumentTargets, getBankCardTargets, documentTargets } from '../config/documentTargets.config.js';
 import { generateEmailPdf } from '../services/pdfService.js';
-import { maybeActivateOnDeliveryConfirmation } from '../services/contractStatusScheduler.service.js';
+import { maybeActivateOnDeliveryConfirmation, withContractDocumentLock } from '../services/contractStatusScheduler.service.js';
 import { DocumentType } from '@prisma/client';
 import prisma from '../lib/prisma.js';
 import path from 'path';
@@ -1876,17 +1877,22 @@ export async function saveEmailAsContractDocument(req: AuthRequest, res: Respons
     const filePath = path.join(uploadsDir, newFilename);
     const relativePath = `/uploads/contract-documents/${newFilename}`;
 
-    fs.writeFileSync(filePath, pdfBuffer);
-
-    const doc = await prisma.contractDocument.create({
-      data: {
-        contractId: contract.id,
-        documentType,
-        documentPath: relativePath,
-        originalName: `${email.subject || 'email'}.pdf`,
-        notes: notes || null,
-        uploadedBy: (req as any).user?.email || 'email-import',
-      },
+    const cleanType = stripHtml(documentType) as string;
+    // Pentest 55.4: Lock vor Schreiben, damit parallele Requests blockieren.
+    // PDF erst INNERHALB des Locks auf Disk schreiben → kein verwaister
+    // Datei-Müll bei Race-Reject.
+    const doc = await withContractDocumentLock(contract.id, cleanType, async () => {
+      fs.writeFileSync(filePath, pdfBuffer);
+      return prisma.contractDocument.create({
+        data: {
+          contractId: contract.id,
+          documentType: cleanType,
+          documentPath: relativePath,
+          originalName: `${email.subject || 'email'}.pdf`,
+          notes: sanitizeNotes(notes),
+          uploadedBy: (req as any).user?.email || 'email-import',
+        },
+      });
     });
 
     // Falls Lieferbestätigung: DRAFT → ACTIVE + startDate setzen falls leer
@@ -2173,17 +2179,20 @@ export async function saveAttachmentAsContractDocument(req: AuthRequest, res: Re
     const filePath = path.join(uploadsDir, newFilename);
     const relativePath = `/uploads/contract-documents/${newFilename}`;
 
-    fs.writeFileSync(filePath, attachment.content);
-
-    const doc = await prisma.contractDocument.create({
-      data: {
-        contractId: contract.id,
-        documentType,
-        documentPath: relativePath,
-        originalName: filename,
-        notes: notes || null,
-        uploadedBy: (req as any).user?.email || 'email-import',
-      },
+    const cleanType = stripHtml(documentType) as string;
+    // Pentest 55.4: Lock vor Schreiben (siehe saveEmailAsContractDocument).
+    const doc = await withContractDocumentLock(contract.id, cleanType, async () => {
+      fs.writeFileSync(filePath, attachment.content);
+      return prisma.contractDocument.create({
+        data: {
+          contractId: contract.id,
+          documentType: cleanType,
+          documentPath: relativePath,
+          originalName: filename,
+          notes: sanitizeNotes(notes),
+          uploadedBy: (req as any).user?.email || 'email-import',
+        },
+      });
     });
 
     // Falls Lieferbestätigung: DRAFT → ACTIVE + startDate setzen falls leer