fix: send unreleased platforms to the installer

A release recorded without a platform's pack linked its button to that release, which serves no pack for AmberELEC, EmuELEC, KNULLI, MinUI, NextUI or MyMinUI. The cell now names the release and points to the installer, which reads the file lists on main. Core folder links resolve each core name to the profile page that describes it (mednafen_vb is beetle_vb).

tests/test_doc_surfaces.py

@@ -112,9 +112,16 @@ class DownloadLinksNameTheFile(unittest.TestCase):
         cell = download_links("batocera", SPLIT_RECORD, REPO, "Pack", " { .x }")
         self.assertEqual(cell.count("{ .x }"), 2)
 
-    def test_without_a_pack_the_link_is_the_release_page(self):
+    def test_a_release_without_the_pack_names_the_installer(self):
         self.assertEqual(
             download_links("bizhawk", SPLIT_RECORD, "../..", "Download"),
+            "Not in v2000.01.01: "
+            "[use the installer](https://abdess.github.io/retrobios/wiki/installer/)",
+        )
+
+    def test_without_a_recorded_release_the_link_is_the_release_page(self):
+        self.assertEqual(
+            download_links("bizhawk", {}, "../..", "Download"),
             "[Download](../../releases/latest)",
         )