test: F2 acceptance — five of FILIUS' examples run as Java FILIUS runs them

ExampleRun opens an example as FILIUS opens it (SzenarioVerwaltung.laden
into the window's lists), starts it as the action mode does, plays a
story and writes every card's frames and tables, the calls, the
addresses and the RIP tables' changes. examplesJava.test.ts reads the
same file with this package's reader and runs it in the core
(projectSnapshot, new): routing (internetwork_komplett), DHCP
(einfaches_rechnernetz_komplett), DNS (dns_server), NAT
(nat_with_mapped_port) and firewall (Internet_Komplett_..._DE) match
card by card.

Found and fixed: a host's ipForwardingEnabled, which Java saves and
obeys, was unknown to the reader, the model, the core, the writer, the
export and FlsOracle; and Java's ARP learns only from a request for its
own address or a reply. Named Java bugs: a ping without a gateway throws
a NullPointerException; a home router drops the answer of a second
remote end. Open: Java picks between equally long RIP routes by thread
timing.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

packages/fls/test/importProject.test.ts

@@ -28,6 +28,7 @@ import {
 import {
   decodeJavaBeans,
   importProject,
+  projectSnapshot,
   readFlsArchive,
   readTopology,
   type FlsApplication,
@@ -708,6 +709,45 @@ describe('importProject rules', () => {
     expect(project.hostWirelessConfigurations.get(withoutNetwork!)).toEqual({ isEnabled: true, ssid: '' });
   });
 
+  it('runs only the DNS servers that are switched on (projectSnapshot)', () => {
+    const dnsServer = (isActive: boolean): FlsApplication => ({ key: 'dns', javaClass: 'filius.software.dns.DNSServer', source: flsNode('Rechner').source, isActive });
+    const project = importProject(
+      topology({
+        nodes: [
+          flsNode('Rechner', { interfaces: [nic('10.0.0.1')], system: { applications: [dnsServer(true)] } }),
+          flsNode('Rechner', { interfaces: [nic('10.0.0.2')], system: { applications: [dnsServer(false)] } }),
+        ],
+      }),
+      counter(),
+    );
+    const [on, off] = project.graph.nodes.map((node) => node.id);
+
+    expect([...project.dnsServerConfigurations.keys()]).toEqual([on, off]);
+    expect([...projectSnapshot(project).dnsServerConfigurationsByNodeId.keys()]).toEqual([on]);
+  });
+
+  it("keeps a node's IP forwarding where it differs from its kind's: a host that forwards, a router that does not", () => {
+    const system = (ipForwardingEnabled: boolean) => ({ manualRoutes: [], ipForwardingEnabled });
+    const project = importProject(
+      topology({
+        nodes: [
+          flsNode('Rechner', { interfaces: [nic('10.0.0.1')], system: system(true) }),
+          flsNode('Notebook', { interfaces: [nic('10.0.0.2')], system: system(false) }),
+          flsNode('Vermittlungsrechner', { portCount: 2, interfaces: [nic('10.0.0.3'), nic('10.1.0.3')], system: system(true) }),
+          flsNode('Vermittlungsrechner', { portCount: 2, interfaces: [nic('10.0.0.4'), nic('10.1.0.4')], system: system(false) }),
+        ],
+      }),
+      counter(),
+    );
+    const [pc, notebook, router, quietRouter] = project.graph.nodes.map((node) => node.id);
+
+    expect([...project.ipForwardingByNodeId]).toEqual([
+      [pc, true],
+      [quietRouter, false],
+    ]);
+    expect([notebook, router].some((id) => project.ipForwardingByNodeId.has(id!))).toBe(false);
+  });
+
   it('takes DHCP settings for hosts and home routers, trimmed, and only when they are not the defaults', () => {
     const defaults = { isActive: false, lowerBound: '0.0.0.0', upperBound: '0.0.0.0', gateway: '0.0.0.0', dnsServer: '0.0.0.0', useOwnSettings: false, staticAssignedAddresses: [] };
     const project = importProject(