Sprint 1 : scaffolding complet de Glibredecision

Plateforme de decisions collectives pour Duniter/G1.
Backend FastAPI async + PostgreSQL (14 tables, 8 routers, 6 services,
moteur de vote avec formule d'inertie WoT/Smith/TechComm).
Frontend Nuxt 4 + Nuxt UI v3 + Pinia (9 pages, 5 stores).
Infrastructure Docker + Woodpecker CI + Traefik.
Documentation technique et utilisateur (15 fichiers).
Seed : Licence G1, Engagement Forgeron v2.0.0, 4 protocoles de vote.
30 tests unitaires (formules, mode params, vote nuance) -- tous verts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/app/models/cache.py

@@ -0,0 +1,18 @@
+import uuid
+from datetime import datetime
+
+from sqlalchemy import String, DateTime, func
+from sqlalchemy.dialects.postgresql import UUID, JSONB
+from sqlalchemy.orm import Mapped, mapped_column
+
+from app.database import Base
+
+
+class BlockchainCache(Base):
+    __tablename__ = "blockchain_cache"
+
+    id: Mapped[uuid.UUID] = mapped_column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
+    cache_key: Mapped[str] = mapped_column(String(256), unique=True, nullable=False, index=True)
+    cache_value: Mapped[dict] = mapped_column(JSONB, nullable=False)
+    fetched_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
+    expires_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), nullable=False)