fix(firewall): Tab-Navigation deutlich besser lesbar

- fw-tabs: Tab-Schrift 13px, font-weight 500, Farbe #64748B (statt AntD-Standard grau)
- Aktiver Tab: #1677ff + font-weight 600 + 2px Unterstrich
- Hover: #334155 für klare Reaktion
- Ink-Bar: 2px Höhe mit abgerundeten Ecken
- Nav-Separator: #E2E8F0 statt default hellgrau

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

management-ui/src/pages/Firewall/index.tsx

@@ -128,6 +128,7 @@ export default function FirewallPage() {
       <Tabs
         items={tabs}
         defaultActiveKey="rules"
+        className="fw-tabs"
       />
     </div>
   )

management-ui/src/styles/enterprise.css

@@ -2918,6 +2918,33 @@ h1, h2, h3, h4, h5, h6 {
 }
 
 /* Filter bar */
+/* ── Firewall Tab-Navigation ─────────────────────────────────────────── */
+.fw-tabs .ant-tabs-nav {
+  margin-bottom: 16px;
+}
+.fw-tabs .ant-tabs-tab {
+  padding: 10px 16px !important;
+  font-size: 13px !important;
+  font-weight: 500 !important;
+  color: #64748B !important;
+  transition: color 0.15s;
+}
+.fw-tabs .ant-tabs-tab:hover {
+  color: #334155 !important;
+}
+.fw-tabs .ant-tabs-tab.ant-tabs-tab-active .ant-tabs-tab-btn {
+  color: #1677ff !important;
+  font-weight: 600 !important;
+}
+.fw-tabs .ant-tabs-ink-bar {
+  height: 2px !important;
+  border-radius: 2px 2px 0 0;
+}
+.fw-tabs .ant-tabs-nav::before {
+  border-bottom-color: #E2E8F0 !important;
+}
+
+/* ── Firewall Filter-Bar ─────────────────────────────────────────────── */
 .fw-filter-bar {
   display: flex;
   gap: 8px;