리노컷 자산 파이프라인 공통화와 캐스트 외형 설계

- P1 전용 스크립트를 docs/avatar-art/linocut-pipeline 으로 옮겨 persona.json 설정으로 일반화(P1 재실행 리그 바이트 동일)
- 7명 외형·상징 설계(linocut-cast.md)와 P2~P7 정면 원화 생성 프롬프트, 얼굴 없는 화풍 참조
- P1 원화 생성 프롬프트 보존

docs/avatar-art/linocut-cast-prompts/P4-front-v2.txt

@@ -0,0 +1,5 @@
+A Korean high-school girl of seventeen, a diligent top student and class president, tense and perfectionistic. Facial structure: a narrow heart-shaped face with a small pointed chin and high cheekbones; long almond-shaped eyes with thin double eyelids, slightly upturned at the outer corners; thin, straight, neatly groomed eyebrows; a narrow straight nose; a small mouth with thin lips pressed tight. Slightly too-alert eyes with faint shadows of sleeplessness. Hair: long straight black hair pulled smoothly straight back from her face and tied in a low ponytail at the nape (the ponytail mostly hidden behind her neck), forehead completely uncovered with no bangs and no hair over the forehead, only a few short baby hairs at her temples. Clothing: a navy crewneck sweater over a white collared shirt with the collar arranged neatly, and a yellow pencil tucked behind her right ear. Very upright posture with stiff, slightly raised shoulders.
+
+She must look like one specific real person with the distinct facial structure described above, not a generic attractive person, and must not resemble anyone else. Natural, realistic Korean facial features: eyes of natural human size (not enlarged), a slightly uneven face, a real nose and lips, natural skin texture. Eyes, eyebrows and mouth are fully visible: no hair, hands or objects over them, and no glasses. Dignified and deeply human. Strictly NOT anime, NOT manga, NOT webtoon, NOT K-pop idol styling, no big shiny eyes, no eyelash emphasis, no glamour. No logos, brand stripes or text on clothing. No marks or wounds on the skin.
+
+Print style, matching the attached texture sample exactly: a linocut relief print with bold carved black-indigo lines and visible gouge marks, flat areas of only two additional ink colors (muted slate blue and warm ochre) printed on cream paper with slight ink texture and imperfect registration; the skin is a flat warm ochre-beige like the neck in the sample. The attached image is only a texture and color sample of the print; it shows no face and gives no facial features. Framing: a portrait of head, neck and shoulders only, centered, facing the viewer straight on (frontal, symmetrical), neutral closed mouth, eyes open looking straight at the viewer, shoulders level, hands out of frame. The top of the hair is about 8% below the top edge, the chin is at about 59% of the image height, and the face is about 48% of the image width. Plain flat cream background with nothing else: no flowers, no clouds, no motifs, no text.