feat(curator): Chinese from CC-CEDICT, with the HSK levels of 2025

Chinese comes from CC-CEDICT (CC BY-SA 4.0), made for learners of
Chinese: `curate cedict` writes two dictionaries of its entries,
`cc-cedict-hans-en` (zh-Hans) and `cc-cedict-hant-en` (zh-Hant), so a
studyset finds its words as it writes them, each finding a word by
either script, by pinyin with or without tones and by its meanings.
Readings are pinyin with tone marks, a syllable to a character; measure
words are a remark beside the meanings.

The HSK levels are those of the 2025 examination syllabus, which HSK
3.0's examination follows since July 2026 (decided 2026-10-14: level
tags, credited), as hsk30 extracted them (MIT): `hsk:1` … `hsk:6`, and
`hsk:7` for 7 to 9, each given to the entry read as the syllabus reads
the word (的 de, not 的 dì; 书 shū, not the Book of Documents, Shū),
ranking the words, HSK 1 first.

`curate update --languages de,el,en,zh` takes over from `--wiktionary`:
Chinese from MDBG's file of the day as often as EDRDG's files, the rest
from Wiktionary's dump.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

halkyon_learn_curator/test/fixtures/README.md

@@ -39,3 +39,8 @@ etymologies or related words; at most six senses, two examples, 40 forms, two
 sounds, and 14 translations, those into German and Greek). Wiktionary's text is
 by its contributors, CC BY-SA 4.0 (<https://en.wiktionary.org/wiki/Wiktionary:Copyrights>);
 the extraction is Tatu Ylonen's Wiktextract (<https://kaikki.org>).
+
+`cedict-sample.txt` holds CC-CEDICT's header and 16 of its lines (MDBG's file of
+2026-10-13): 中国, 了, 女儿, 学习, 书, 熊猫, 略, 的, 说 and 银行, with their
+readings. CC-CEDICT is by MDBG and its contributors, CC BY-SA 4.0
+(<https://www.mdbg.net/chinese/dictionary?page=cc-cedict>).