feat: system settings, dynamic logos, template numbering, permission consolidation

- System settings page with tabs: Security, System, Firma
- Configurable attendance rules (break thresholds, rounding) from DB
- Configurable document numbering with template patterns ({YYYY}/{PREFIX}/{NNN})
- Dynamic logo upload (light/dark variants) served from DB instead of static files
- Email settings (SMTP from/name, alert/leave emails) configurable in UI
- Currency and VAT rate lists configurable, used across all modules
- Permissions simplified: offers.settings + settings.roles + settings.security → settings.manage
- Leaflet bundled locally, removed unpkg.com from CSP
- Silent catch blocks fixed with proper logging
- console.log replaced with app.log.info in server.ts
- Schema renamed: company-settings.schema → settings.schema
- App info section: version, Node.js, uptime, memory, DB status, NAS status

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

src/admin/pages/Offers.tsx

@@ -324,7 +324,7 @@ export default function Offers() {
           </p>
         </div>
         <div className="admin-page-actions">
-          {hasPermission("offers.settings") && (
+          {hasPermission("settings.manage") && (
             <Link
               to="/offers/templates"
               className="admin-btn admin-btn-secondary"