fix(desktop): probe GameMaker data filenames

Select conventional Linux and macOS game data files for the existing bounded FORM/GEN8 probe. Add service-boundary regressions and document the selected names.

Fixes #6659

docs/desktop-applications.md

@@ -97,7 +97,7 @@ same bundle. Export writes only the caller-selected output file.
 | Unity Mono   | A managed assembly below `*_Data/Managed` or `Contents/Resources/Data/Managed` has an exact UnityEngine assembly reference.                                                                                                                    |
 | Unity IL2CPP | A recognized IL2CPP metadata magic (with the raw version when complete) coexists with a conventionally named native `GameAssembly.dll`, `GameAssembly.so`, `GameAssembly.dylib` or `libil2cpp.so` image. Build correspondence remains unknown. |
 | Godot        | A `GDPC` header at file start or a validated executable trailer offset.                                                                                                                                                                        |
-| GameMaker    | A bounded `FORM` container starts with a `GEN8` chunk.                                                                                                                                                                                         |
+| GameMaker    | A bounded `FORM` container starts with a `GEN8` chunk. The scan probes conventional `data.win`, `game.unx`, and `game.ios` data files for that header.                                                                                          |
 | Unreal       | `Content/Paks` path conventions or an IoStore TOC signature; arbitrary `.pak` filenames are insufficient.                                                                                                                                      |
 | Electron     | A `resources/app.asar` or `resources/default_app.asar` path convention; archive validity is unverified.                                                                                                                                        |
 

src/artifacts/DesktopApplicationReader.ts

@@ -476,6 +476,6 @@ const addPathFacts = (row: DesktopFile): string | null => {
 
 const probeSelected = (entry: DirectoryArtifactEntry): boolean =>
   entry.executable ||
-  /(?:\.(?:exe|dll|so|dylib|pck|utoc)|(?:^|\/)global-metadata\.dat|(?:^|\/)data\.win)$/iu.test(
+  /(?:\.(?:exe|dll|so|dylib|pck|utoc)|(?:^|\/)(?:global-metadata\.dat|data\.win|game\.(?:unx|ios)))$/iu.test(
     entry.path,
   );

tests/boundary/filesystem/desktopApplication.test.ts

@@ -787,6 +787,38 @@ it.each([
   },
 );
 
+it.each([
+  "assets/game.unx",
+  "Example.app/Contents/Resources/game.ios",
+])("probes the GameMaker data file at %s", async (path) => {
+  const root = await createTestTempDirectory("rea-desktop-gamemaker-data-");
+  const form = Buffer.alloc(16);
+  form.write("FORM");
+  form.writeUInt32LE(8, 4);
+  form.write("GEN8", 8);
+  form.writeUInt32LE(0, 12);
+  await put(root, path, form);
+
+  const { report } = await inspect(root);
+  expect(report.candidates.map((candidate) => candidate.family)).toContain(
+    "gamemaker",
+  );
+  expect(report.files).toContainEqual(
+    expect.objectContaining({
+      path,
+      read_status: "examined",
+      facts: [
+        expect.objectContaining({
+          kind: "gamemaker-form-header",
+          offset: 0,
+          value: { container: "FORM", first_chunk: "GEN8" },
+        }),
+      ],
+    }),
+  );
+  expect(report.coverage.status).toBe("complete-within-scan");
+});
+
 it("compares exact signature bytes without masking high bits in engine headers or trailers", async () => {
   const root = await createTestTempDirectory("rea-desktop-exact-signatures-");
   const pck = Buffer.alloc(20);