feat(curator): characters of Chinese and Korean, the Greek alphabet, Korean words from KRDict

For parity with Japanese's KANJIDIC2 and kana:

- Unihan (Unicode License v3) makes characters' dictionaries: the 8,105
  standard simplified characters (unihan-hans) and the traditional ones in
  use (unihan-hant), told apart and ranked by CC-CEDICT's words (Unihan
  calls 这 its own traditional variant; 後 ranks as the 后 of 以后), with
  pinyin, meanings, strokes, Kangxi radical, HSK 2025 character levels,
  the 3,500 common ones and Hong Kong's grades; and Korean Hanja
  (unihan-ko) with their sounds, the 1,800 of education, and their native
  readings from Wiktionary (물 수), with the 40 Hangul letters as kana are.
- The Greek alphabet, the curator's own (CC0): letters with names,
  transliteration and sound.
- KRDict, the Basic Korean Dictionary for learners (CC BY-SA 2.0 KR,
  downloaded without an account), replaces Wiktionary for Korean's words:
  learners' levels, pronunciation where it differs from the spelling
  (같이 [가치]), Hanja, English senses; Wiktionary's update keeps the
  words' forms (가다's 99) and the Hanja's readings beside it for both.
- The update converts KRDict when its page offers another export and the
  characters weekly, and removes the files of languages no longer kept
  or of sources replaced.

Measured on the real data: Unihan 3 s; KRDict 54,870 entries in 24 s
and under 600 MB.

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/wiktionary-sample.jsonl

@@ -28,3 +28,4 @@
 {"senses": [{"examples": [{"text": "작품(作品) (jakpum, “works”) + 집(集) (jip, “collection”) → 작품집(作品集) (jakpumjip, “collected works”)", "type": "example"}], "glosses": ["collection of bound works; anthology, collected works"], "tags": ["morpheme"]}], "pos": "suffix", "head_templates": [{"name": "ko-suffix", "args": {"hanja": "集"}, "expansion": "—집 • (-jip) (hanja 集)"}], "forms": [{"form": "—집", "tags": ["canonical"]}, {"form": "-jip", "tags": ["romanization"]}, {"form": "集", "tags": ["hanja"]}], "etymology_number": "2", "word": "집", "lang": "Korean", "lang_code": "ko"}
 {"senses": [{"examples": [{"text": "최근에 박사 과정을 시작했는데 다시 학생이 돼서 기분이 좋습니다.", "bold_text_offsets": [[20, 23]], "roman": "Choegeun-e baksa gwajeong-eul sijakhaenneunde dasi haksaeng-i dwaeseo gibun-i joseumnida.", "bold_roman_offsets": [[51, 61]], "translation": "I recently started a PhD program, and it feels good to be a student again.", "english": "I recently started a PhD program, and it feels good to be a student again.", "bold_translation_offsets": [[60, 67]], "type": "example"}], "glosses": ["student, scholar, school pupil"]}], "pos": "noun", "head_templates": [{"name": "ko-noun", "args": {"hanja": "學生", "count": "명(名)"}, "expansion": "학생 • (haksaeng) (counter 명(名), hanja 學生)"}], "forms": [{"form": "haksaeng", "tags": ["romanization"]}, {"form": "명", "tags": ["counter", "error-unknown-tag"]}, {"form": "學生", "tags": ["hanja"]}], "sounds": [{"tags": ["SK-Standard", "Seoul"], "ipa": "[ha̠ks͈ɛŋ]"}, {"tags": ["SK-Standard", "Seoul"], "ipa": "[ha̠ks͈e̞ŋ]"}], "word": "학생", "lang": "Korean", "lang_code": "ko"}
 {"senses": [{"glosses": ["contraction of in + dem; in the"], "tags": ["abbreviation", "alt-of", "contraction"], "alt_of": [{"word": "in", "extra": "+ dem; in the"}]}], "pos": "contraction", "head_templates": [{"name": "head", "args": {"1": "de", "2": "contraction"}, "expansion": "im"}], "forms": [{"form": "no-table-tags", "source": "declension", "tags": ["table-tags"]}, {"form": "l", "source": "declension", "tags": ["inflection-template"]}, {"form": "in den", "tags": ["accusative", "masculine"], "source": "declension"}, {"form": "ins", "tags": ["accusative", "neuter"], "source": "declension"}, {"form": "in die", "tags": ["accusative", "feminine"], "source": "declension"}, {"form": "in die", "tags": ["accusative", "plural"], "source": "declension"}, {"form": "im", "tags": ["dative", "masculine"], "source": "declension"}, {"form": "im", "tags": ["dative", "neuter"], "source": "declension"}, {"form": "in der", "tags": ["dative", "feminine"], "source": "declension"}, {"form": "in den", "tags": ["dative", "plural"], "source": "declension"}], "sounds": [{"ipa": "/ɪm/"}, {"audio": "De-im.ogg", "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/7/71/De-im.ogg", "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/7/71/De-im.ogg/De-im.ogg.mp3"}, {"audio": "De-im2.ogg", "tags": ["Germany", "Berlin"], "ogg_url": "https://upload.wikimedia.org/wikipedia/commons/4/44/De-im2.ogg", "mp3_url": "https://upload.wikimedia.org/wikipedia/commons/transcoded/4/44/De-im2.ogg/De-im2.ogg.mp3"}], "word": "im", "lang": "German", "lang_code": "de"}
+{"word": "水", "pos": "character", "lang": "Korean", "lang_code": "ko", "forms": [{"form": "물 수", "roman": "mul su", "tags": ["eumhun"]}], "head_templates": [{"name": "ko-hanja", "args": {"1": "물", "2": "수"}, "expansion": "水 (eumhun 물 수 (mul su))"}], "senses": [{"glosses": ["hanja form of 수 (“water”)"], "tags": ["form-of", "hanja"]}, {"glosses": ["hanja form of 수 (“short for 수요일(水曜日) (suyoil, “Wednesday”)”)"], "tags": ["form-of", "hanja"]}]}