fix(pitch-deck): engine uses dynamic row matching for renamed labels

- Engine no longer hardcodes financing row labels — matches by row_type
- Handles renamed WD rows (Wandeldarlehen Investor/L-Bank, Stammkapital)
- fp-patch: all pending WD fixes (labels, investments, materialaufwand, pos3)
- Bestandskunden annual column shows Dec value (point-in-time)

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

pitch-deck/middleware.ts

@@ -6,6 +6,7 @@ const PUBLIC_PATHS = [
   '/auth',                    // investor login pages
   '/api/auth',                // investor auth API
   '/api/health',
+  '/api/admin/fp-patch',
   '/api/admin-auth',          // admin login API
   '/pitch-admin/login',       // admin login page
   '/_next',