docs: render without deprecated optionsDocBook

The `optionsDocBook` function is deprecated in nixpkgs since
nixos-23.11. This commit updates the manual and manpages to
use commonmark formatted documentation instead of the deprecated
docbook format.

docs/home-manager-render-docs/home_manager_render_docs/__init__.py

@@ -0,0 +1,55 @@
+import argparse
+import sys
+import textwrap
+import traceback
+from io import StringIO
+from pprint import pprint
+
+from nixos_render_docs import manual
+from . import options
+from nixos_render_docs import parallel
+
+def pretty_print_exc(e: BaseException, *, _desc_text: str = "error") -> None:
+    print(f"\x1b[1;31m{_desc_text}:\x1b[0m", file=sys.stderr)
+    # destructure Exception and RuntimeError specifically so we can show nice
+    # messages for errors that weren't given their own exception type with
+    # a good pretty-printer.
+    if type(e) is Exception or type(e) is RuntimeError:
+        args = e.args
+        if len(args) and isinstance(args[0], str):
+            print("\t", args[0], file=sys.stderr, sep="")
+            args = args[1:]
+        buf = StringIO()
+        for arg in args:
+            pprint(arg, stream=buf)
+        if extra_info := buf.getvalue():
+            print("\x1b[1;34mextra info:\x1b[0m", file=sys.stderr)
+            print(textwrap.indent(extra_info, "\t"), file=sys.stderr, end="")
+    else:
+        print(e)
+    if e.__cause__ is not None:
+        print("", file=sys.stderr)
+        pretty_print_exc(e.__cause__, _desc_text="caused by")
+
+def main() -> None:
+    parser = argparse.ArgumentParser(description='render nixos manual bits')
+    parser.add_argument('-j', '--jobs', type=int, default=None)
+
+    commands = parser.add_subparsers(dest='command', required=True)
+
+    options.build_cli(commands.add_parser('options'))
+    manual.build_cli(commands.add_parser('manual'))
+
+    args = parser.parse_args()
+    try:
+        parallel.pool_processes = args.jobs
+        if args.command == 'options':
+            options.run_cli(args)
+        elif args.command == 'manual':
+            manual.run_cli(args)
+        else:
+            raise RuntimeError('command not hooked up', args)
+    except Exception as e:
+        traceback.print_exc()
+        pretty_print_exc(e)
+        sys.exit(1)