feat(fls): DNS records from /dns/hosts, as Java's server answers them

Java's DNS server reads its records from the text file /dns/hosts on every
query. dnsHosts.ts ports that reading (DNSServer.leseRecordListe,
ResourceRecord, Dateisystem.holeDatei) and keeps in the model the records
Java answers: type exactly A, MX or NS, and a name Java accepted. The file
stays in the file system as it is.

Both oracles read 76 hand-picked hosts files (dns-hosts.cases.txt): the
Java oracle through DNSServer.holeResourceRecords (DnsHostsCases), the
Swift oracle through TopologyDNSHostsFileCodec (--dns-hosts). The Java view
matches Java on every case; the model matches Swift except for 33 named
cases in twelve reasons: Java splits at single spaces and LF only, has no
comments or "IN", turns a TTL that is no int into 3600, keeps duplicates,
and empties names with a leading digit. The Swift dump now carries each
server's records; the corpus comparison covers them on 16 files.

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

packages/fls/src/importProject.ts

@@ -33,7 +33,10 @@
 //  - a web server's files stay in /webserver (its document root), where Swift
 //    moves them to /www; and no program state is written into a host's files
 //    (Swift keeps Gnutella and e-mail state there as hidden JSON files).
-// Not here yet: DNS records (from /dns/hosts) and e-mail accounts.
+//  - a DNS server's records are what Java's server answers from /dns/hosts
+//    (see dnsHosts.ts); Swift reads the file its own way — tabs, comments,
+//    "IN", names with a leading digit — and drops Java's duplicates.
+// Not here yet: e-mail accounts.
 
 import {
   canonicalMacAddress,
@@ -88,6 +91,7 @@ import {
   type TopologyNode,
   type VirtualFileContent,
 } from '@mdg-filius/core';
+import { dnsRecordsOf, javaHostsFileContent, readJavaDnsHosts } from './dnsHosts.js';
 import type { FlsApplicationClass, FlsFileTree, FlsFirewall } from './systemSoftware.js';
 import type { FlsDocumentationItem, FlsInterface, FlsNode, FlsNodeClass, FlsTopology } from './topology.js';
 
@@ -415,11 +419,15 @@ function registerPrograms(source: FlsNode, node: TopologyNode, system: SystemCon
         const forwarder = trimmedOrEmpty(source.interfaces[0]?.dns);
         const primary = trimmedOrEmpty(source.interfaces[0]?.ip);
         const forwarding = recursive && forwarder !== '' && forwarder !== primary;
+        const hosts = javaHostsFileContent(source.system.fileSystem);
+        const records = dnsRecordsOf(readJavaDnsHosts(hosts ?? ''), (message) =>
+          warnings.push(`node '${node.displayName}': ${message}`),
+        );
         system.dnsServerConfigurations.set(
           node.id,
           forwarding
-            ? { recursiveResolutionEnabled: recursive, forwardingServerIPAddress: forwarder }
-            : { recursiveResolutionEnabled: recursive },
+            ? { recursiveResolutionEnabled: recursive, forwardingServerIPAddress: forwarder, records }
+            : { recursiveResolutionEnabled: recursive, records },
         );
         break;
       }