feat(fls): system software settings as Java loads them

readSystemSoftware adds to each node what the topology needs from its
system software: a switch's SSID and learning time, a host's wireless
SSID, a router's RIP switch, the manual routes and the firewall of a
router or home router. All 23 corpus files match Java.

- A router's firewall is one object its constructor hangs in two places;
  the corpus writes it under the web server's "konfig" plug-in. The
  places are merged.
- The decoder keeps entries a constructor made in a map, reached by
  get(key) (installed applications), like the elements of a list.
- The Java oracle loads every file twice and writes values that differ
  as null: what FILIUS rolls (MACs, a switch's SSID) without text search.

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

packages/fls/test/javabeans.test.ts

@@ -186,6 +186,33 @@ describe('XMLDecoder rules', () => {
     expect(listItems(list)).toHaveLength(3);
   });
 
+  it("keeps the entries a constructor made in a map, reached by get(key), and shares them", () => {
+    // A router's operating system installs its web server in the constructor;
+    // the file reaches it through the map and changes it.
+    const [system] = decodeJavaBeans(
+      doc(`<object class="filius.software.system.VermittlungsrechnerBetriebssystem">
+             <void id="HashMap0" property="installierteAnwendungen">
+               <void id="WebServer0" method="get"><string>filius.software.www.WebServer</string>
+                 <void property="aktiv"><boolean>true</boolean></void>
+               </void>
+               <void method="get"><string>filius.software.www.WebServer</string>
+                 <void property="port"><int>8080</int></void>
+               </void>
+               <void method="put"><string>extra</string><int>1</int></void>
+             </void>
+           </object>`),
+    );
+
+    const entries = mapEntries(object(system).properties.get('installierteAnwendungen'));
+    expect(entries.map(([key]) => key)).toEqual(['filius.software.www.WebServer', 'extra']);
+    const server = object(entries[0]![1]);
+    expect(server).toMatchObject({ className: 'WebServer', id: 'WebServer0', fromGetter: true });
+    expect([...server.properties]).toEqual([
+      ['aktiv', true],
+      ['port', 8080],
+    ]);
+  });
+
   it('replays add at an index and set by index in order', () => {
     const [list] = decodeJavaBeans(
       doc(`<object class="java.util.ArrayList">