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/services/document_service.py

@@ -0,0 +1,108 @@
+"""Document service: retrieval and version management."""
+
+from __future__ import annotations
+
+import uuid
+
+from sqlalchemy import select
+from sqlalchemy.ext.asyncio import AsyncSession
+from sqlalchemy.orm import selectinload
+
+from app.models.document import Document, DocumentItem, ItemVersion
+
+
+async def get_document_with_items(slug: str, db: AsyncSession) -> Document | None:
+    """Load a document with all its items and their versions, eagerly.
+
+    Parameters
+    ----------
+    slug:
+        Unique slug of the document.
+    db:
+        Async database session.
+
+    Returns
+    -------
+    Document | None
+        The document with items and versions loaded, or None if not found.
+    """
+    result = await db.execute(
+        select(Document)
+        .options(
+            selectinload(Document.items).selectinload(DocumentItem.versions)
+        )
+        .where(Document.slug == slug)
+    )
+    return result.scalar_one_or_none()
+
+
+async def apply_version(
+    item_id: uuid.UUID,
+    version_id: uuid.UUID,
+    db: AsyncSession,
+) -> DocumentItem:
+    """Apply an accepted version to a document item.
+
+    This replaces the item's current_text with the version's proposed_text
+    and marks the version as 'accepted'.
+
+    Parameters
+    ----------
+    item_id:
+        UUID of the DocumentItem to update.
+    version_id:
+        UUID of the ItemVersion to apply.
+    db:
+        Async database session.
+
+    Returns
+    -------
+    DocumentItem
+        The updated document item.
+
+    Raises
+    ------
+    ValueError
+        If the item or version is not found, or the version does not
+        belong to the item.
+    """
+    # Load item
+    item_result = await db.execute(
+        select(DocumentItem).where(DocumentItem.id == item_id)
+    )
+    item = item_result.scalar_one_or_none()
+    if item is None:
+        raise ValueError(f"Element de document introuvable : {item_id}")
+
+    # Load version
+    version_result = await db.execute(
+        select(ItemVersion).where(ItemVersion.id == version_id)
+    )
+    version = version_result.scalar_one_or_none()
+    if version is None:
+        raise ValueError(f"Version introuvable : {version_id}")
+
+    if version.item_id != item.id:
+        raise ValueError(
+            f"La version {version_id} n'appartient pas a l'element {item_id}"
+        )
+
+    # Apply the version
+    item.current_text = version.proposed_text
+    version.status = "accepted"
+
+    # Mark all other pending/voting versions for this item as rejected
+    other_versions_result = await db.execute(
+        select(ItemVersion).where(
+            ItemVersion.item_id == item_id,
+            ItemVersion.id != version_id,
+            ItemVersion.status.in_(["proposed", "voting"]),
+        )
+    )
+    for other_version in other_versions_result.scalars():
+        other_version.status = "rejected"
+
+    await db.commit()
+    await db.refresh(item)
+
+    return item