Hayagriva sorts Biblatex UTF8 entries incorrectly

[ironupiwada]

Currently, Hayagriva seems to completely ignore the sorting of Biblatex entries according to the UTF8 rules. Consider the following example, based on custom CSL:

// Example bibliography

@Newspaper{AmbroiseRendu1986,
  author       = {Ambroise-Rendu, Marc},
  date         = {1986-06-28},
  publisher = {„Le Monde”},
  title        = {M. Chirac confie à une société d'économie mixte l'alimentation en eau de Paris},
  url          = {https://archive.li/7YZrO},
  urldate      = {2023-02-15},
  language        = {fr},
}
@Book{LeRoux2022,
  author    = {{Le Roux}, Nicolas},
  date      = {2022},
  title     = {1559-1629: Les guerres de Religion},
  location  = {Paris},
  publisher = {Gallimard},
  language     = {fr},
  origdate  = {2009},
}
@video{Robson1987Crash,
	author = {{Ère Informatique}},
	date = {1987},
	location = {{Francja}},
	publisher = {{Ère Informatique}},
	title = {Crash {{Garrett}}},
	version = {{Amiga}}
}
@book{lakomyFrancoisMitterandBiografia2006,
	author = {Łakomy, Henryk},
	date = {2006},
	language = {pl},
	location = {{Kraków}},
	publisher = {{Wydawnictwo Naukowe Akademii Pedagogicznej}},
	shorttitle = {François Mitterand},
	title = {François Mitterand. Biografia polityczna}
}
@book{zizekTarryingNegativeKant1993,
	abstract = {viii, 289 p. ; 24 cm; Includes bibliographical references (p. [239]-285) and index},
	author = {Žižek, Slavoj},
	date = {1993},
	isbn = {978-0-8223-1362-5},
	keywords = {Kant, Immanuel, 1724-1804},
	language = {en},
	location = {{Durham}},
	publisher = {{Duke University Press}},
	shorttitle = {Tarrying with the {{Negative}}},
	title = {Tarrying with the {{Negative}}: {{Kant}}, {{Hegel}}, and the {{Critique}} of {{Ideology}}}
}

// Example entries

#lorem(20)
@AmbroiseRendu1986
@Robson1987Crash
@lakomyFrancoisMitterandBiografia2006
@LeRoux2022
@zizekTarryingNegativeKant1993

#bibliography("references.bib", style: "uj.csl", title: none)

As you can see, Hayagriva does not recognize UTF8 letters such as Polish "Ł" and French "È" while sorting the entries (Łakomy should be rendered before Roux). Would it be possible to resolve this bug or find a workaround?