배치 실행, 그리고 끊겨도 되는 기술

def fresh(path: Path, force: bool) -> bool:
    """Naive: is there something already at this path?"""
    return path.exists() and not force


# The problem: edit the scene, and this still says True.
# The fix is not a smarter check - it is a different address.

def scene_digest(sc: dict) -> str:
    """Everything that can change the pixels goes into the key."""
    payload = json.dumps(sc, sort_keys=True, ensure_ascii=False)
    return hashlib.sha256(payload.encode()).hexdigest()[:12]


def scene_plate_path(ep: Path, sc: dict) -> Path:
    # content-keyed: editing a scene cannot serve last run's pixels,
    # because the edited scene simply has a different filename.
    return ep / "plates" / f"{sc['key']}-{scene_digest(sc)}.png"


def scene_clip_path(ep: Path, sc: dict, dur: float) -> Path:
    # keyed by the scene AND its length on the timeline - the same
    # picture held for 4s and for 9s are two different artifacts.
    return ep / "clips" / f"{sc['key']}-{scene_digest(sc)}-{dur:.2f}.mp4"

# a full run: each stage caches its outputs
pipeline.py all --episode my-episode

# ...dies during encode. re-invoke; synthesis and plates are kept.
pipeline.py all --episode my-episode

# rebuild one stage on purpose
pipeline.py plates --episode my-episode --force

# one bad speech take: purge exactly that segment, keep the rest.
# without this, re-synthesizing identical text is a cache hit
# that cheerfully returns the same glitched audio forever.
pipeline.py reroll seg-014 --episode my-episode