chore: follow site tests to the rescraped data

Each change records a fact the data no longer states:

- ROCKNIX 20261101 dropped the AetherSX2 package, so the install box
  names KNULLI alone.
- RetroBat no longer pins an md5 on ar_bios.zip for the Arcadia, so no
  file is held for emerson-arcadia-2001 and its UNLINKED entry is gone.
- sega-model1 holds only the model1io and model1io2 device sets, filed
  under Arcade > Arcade and Arcade > MAME, with no section of its own.
- The Sega page gained Model 2 and new Chihiro and Hikaru files on the
  same card layout: its word ceiling is measured again at 3545.

tests/test_site_density_cards.py

@@ -280,12 +280,14 @@ class TheScriptWiresBoth(unittest.TestCase):
 
 
 # Visible words of each built page: measured before the round and after it,
-# the ceiling being the after value with 5 % of room.
+# the ceiling being the after value with 5 % of room. A page whose content
+# grew is measured again on the same layout: Sega on 2026-11-09, with Model 2
+# and new Chihiro and Hikaru files.
 WORD_CEILINGS = {
     "systems/sony": (2012, 1407),
     "systems/sony-playstation": (2709, 2130),
     "systems/nintendo": (3598, 2941),
-    "systems/sega": (4151, 3370),
+    "systems/sega": (4151, 3545),
     "emulators/duckstation": (1188, 1117),
     "emulators/yaps2": (3159, 2655),
 }

tests/test_site_emulators.py

@@ -511,8 +511,9 @@ class TheBuiltEmulatorPages(unittest.TestCase):
         page = self._html("emulators/aethersx2")
         self.assertRegex(page, r'Download <a href="[^"]*/systems/sony[^"]*#sha1-[0-9a-f]{12}"')
         # The command only where a setup launches AetherSX2 itself (KNULLI,
-        # ROCKNIX), never through RetroArch's folder, which the app never reads.
-        self.assertIn("With ROCKNIX or KNULLI:", page)
+        # ROCKNIX dropped the package in 20261101), never through RetroArch's
+        # folder, which the app never reads.
+        self.assertIn("With KNULLI:", page)
         self.assertNotIn("RetroArch", page.split("Install this emulator", 1)[1].split("</details>", 1)[0])
 
     def test_the_index_leaves_the_template_out(self):

tests/test_site_system_sections.py

@@ -44,13 +44,13 @@ UNLINKED: dict[str, str] = {
     "omicron": "Other > omicron",
     "rpgmaker": "RPG Maker > easyrpg",
     "sdlpal": "the SDLPAL section under its own top, named after the program",
+    "sega-model1": "Arcade > Arcade and Arcade > MAME: the I/O board device sets",
     "sega-system16b": "Arcade > FBNeo, and isgsm.zip is also the ISG Selection Master's",
     "smbx": "Game Engines > TheXTech",
     "thomson-mo6": "Other > Clock Signal",
     "vgmplay": "qsound.zip, ym2413.zip, ym2608.zip: sound chips, no board",
     # Files filed with another machine: a link would name the wrong one.
     "commodore-c64-supercpu": "VICE's tree under the C128",
-    "emerson-arcadia-2001": "ar_bios.zip is filed with the Saturn",
     "spectravideo": "the SVI ROMs are filed with the MSX",
     "taito-type-x": "mame2010 files taitogn.zip, the G-NET BIOS, under this id",
     "vvvvvv": "SDL's controller database",