feat: logos, build stamps and exact wording

- The installer says "Every file on the list is in place." where it
  said "Everything is in place.": a check covers the files the
  collection holds, and the required ones it lacks follow.
- The FAQ, first install, legal and home pages state only what the
  code shows (PlayStation 1 and Saturn run without a BIOS on some
  emulators, save files are never touched, records are added).
- MinUI and MyMinUI show their own boot logos, and the Android,
  Linux handheld and iPhone tiles show the Android robot, Tux and a
  plain device icon, each credited in sources.json.
- Each Markdown copy, llms.txt and llms-full.txt name the commit
  they were built from, version.json the current one, and the
  answering rules tell assistants to fetch a stale copy again.
- The deploy lists the pages whose words changed (digests.json) and
  posts them to IndexNow once the site is live.

scripts/generate_installer_doc.py

@@ -586,7 +586,8 @@ def sample_writers(box: Sandbox) -> dict[str, Callable[[str], str]]:
             f"{list_date('retroarch')}:\n\n"
             + _fenced([_bulk_line(box)])),
         "run-check": lambda _body: _fenced(
-            _lines_from(check_run(), "Checking existing files", "  Everything is in place")),
+            _lines_from(check_run(), "Checking existing files",
+                        "  Every file on the list is in place")),
         "check-refused": lambda _body: _fenced(_refused_lines(box.small("refused"))),
         "from-run": lambda _body: _fenced(
             _lines_from(box.small("from"), "Done.", count=2)),