feat(fls): keep a .fls's own applications through the editor model

The archive's entries besides the configuration — the project's own Java
applications under projekt/anwendungen (.java, .class,
EigeneAnwendungen.txt) — now go through the editor model:
openProjectArchive reads a whole .fls into the model and keeps them in its
archiveEntries, saveProjectArchive writes a whole .fls from the model with
them unchanged. They cannot run here, but must not be lost.

Checked on every corpus file: each entry comes back byte for byte (7 files
carry applications of their own); a probe that drops them is caught.
Installing such applications on a host is the next step; Java loads those
only through its full loading path, which the oracle is to use first.

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

packages/fls/test/exported.java.json

@@ -8230,7 +8230,7 @@
       }
     ],
     "documentation": [],
-    "sha256": "e0f906a2f02c2fdb9b309a6fc0c5625113270ffa95a7a1ce8be11f93e146bd2c"
+    "sha256": "955edc9322d1de6bae59ce05221b94ab18983c46193db034cf37fd18f0146a48"
   },
   "java-examples/dhcp_test_scenario.fls": {
     "success": true,
@@ -8650,7 +8650,7 @@
       }
     ],
     "documentation": [],
-    "sha256": "76d8317e6d352e8686663957f0bbc74f1945b0c419a80ac94992e40590e75e8c"
+    "sha256": "24841ef8e02136eef19247c1a53850c4644232d97a016815bd2338e8190bd357"
   },
   "java-examples/dns_server.fls": {
     "success": true,
@@ -10024,7 +10024,7 @@
       }
     ],
     "documentation": [],
-    "sha256": "ebd1aad2945a178470cc22ce327460d09c456814dbcd155eacced456f242661b"
+    "sha256": "bc7b13a0ada9522a211583371d9b838c4731642032efa1d49d8c217903e4b989"
   },
   "java-examples/email_komplett.fls": {
     "success": true,
@@ -13451,7 +13451,7 @@
       }
     ],
     "documentation": [],
-    "sha256": "35e84042bc6b04062cb943127a85900ebbc947d5148e9fbf4978bb128a013ff3"
+    "sha256": "b860d1bdf773a92b90f63ff6c7c76e9d0ee2c9b342e6042c3e39f61acf6697e3"
   },
   "java-examples/nat.fls": {
     "success": true,
@@ -17079,7 +17079,7 @@
       }
     ],
     "documentation": [],
-    "sha256": "f9f829093450eda122c1a5c01d66b1492fd426769652d1f138791a56641d1fea"
+    "sha256": "ff743751be0d5ecdd84d1db935a332c248e39d1f6f7d3882efdb108c419a0a38"
   },
   "java-examples/zwei_rechnernetze_komplett.fls": {
     "success": true,
@@ -18359,14 +18359,14 @@
       }
     ],
     "documentation": [],
-    "sha256": "ebd1aad2945a178470cc22ce327460d09c456814dbcd155eacced456f242661b"
+    "sha256": "bc7b13a0ada9522a211583371d9b838c4731642032efa1d49d8c217903e4b989"
   },
   "java-tests/empty.fls": {
     "success": true,
     "nodes": [],
     "cables": [],
     "documentation": [],
-    "sha256": "49855a61d8576af64e50c211807e658d69daa924a411ced654a3452070b1722c"
+    "sha256": "aec202d78dc3a05cd83471744050a102cb2cf448b273b053df6b4c640f1ac6e9"
   },
   "synthetic/model.fls": {
     "success": true,