nixos-render-docs: don't render options during manual parsing

we should really be rendering options at *rendering* time, not at parse
time. currently this is just an academic exercise, but the html renderer
will have to inspect the options.json data after the entire document has
been parsed, but before anything gets rendered.

pkgs/tools/nix/nixos-render-docs/src/nixos_render_docs/manual.py

@@ -97,7 +97,10 @@ class ManualDocBookRenderer(DocBookRenderer):
                 raise RuntimeError(f"rendering {path}") from e
         return "".join(result)
     def included_options(self, token: Token, tokens: Sequence[Token], i: int) -> str:
-        return cast(str, token.meta['rendered-options'])
+        conv = options.DocBookConverter(self._manpage_urls, self._revision, False, 'fragment',
+                                        token.meta['list-id'], token.meta['id-prefix'])
+        conv.add_options(token.meta['source'])
+        return conv.finalize(fragment=True)
 
     # TODO minimize docbook diffs with existing conversions. remove soon.
     def paragraph_open(self, token: Token, tokens: Sequence[Token], i: int) -> str:
@@ -181,11 +184,10 @@ class DocBookConverter(Converter[ManualDocBookRenderer]):
                 " ".join(items.keys()))
 
         try:
-            conv = options.DocBookConverter(
-                self._renderer._manpage_urls, self._renderer._revision, False, 'fragment', varlist_id, id_prefix)
             with open(self._base_paths[-1].parent / source, 'r') as f:
-                conv.add_options(json.load(f))
-            token.meta['rendered-options'] = conv.finalize(fragment=True)
+                token.meta['id-prefix'] = id_prefix
+                token.meta['list-id'] = varlist_id
+                token.meta['source'] = json.load(f)
         except Exception as e:
             raise RuntimeError(f"processing options block in line {token.map[0] + 1}") from e