Sprint 2 : moteur de documents + sanctuaire

Backend:
- CRUD complet documents/items/versions (update, delete, accept, reject, reorder)
- Service IPFS (upload/retrieve/pin via kubo HTTP API)
- Service sanctuaire : pipeline SHA-256 + IPFS + on-chain (system.remark)
- Verification integrite des entrees sanctuaire
- Recherche par reference (document -> entrees sanctuaire)
- Serialisation deterministe des documents pour archivage
- 14 tests unitaires supplementaires (document service)

Frontend:
- 9 composants : StatusBadge, MarkdownRenderer, DiffView, ItemCard,
  ItemVersionDiff, DocumentList, SanctuaryEntry, IPFSLink, ChainAnchor
- Page detail item avec historique des versions et diff
- Page detail sanctuaire avec verification integrite
- Modal de creation de document + proposition de version
- Archivage document vers sanctuaire depuis la page detail

Documentation:
- API reference mise a jour (9 nouveaux endpoints)
- Guides utilisateur documents et sanctuaire enrichis

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

backend/app/schemas/document.py

@@ -60,6 +60,15 @@ class DocumentItemCreate(BaseModel):
     voting_protocol_id: UUID | None = None
 
 
+class DocumentItemUpdate(BaseModel):
+    """Partial update for a document item."""
+
+    title: str | None = Field(default=None, max_length=256)
+    current_text: str | None = Field(default=None, min_length=1)
+    position: str | None = Field(default=None, max_length=16)
+    item_type: str | None = Field(default=None, max_length=32)
+
+
 class DocumentItemOut(BaseModel):
     """Full document item representation."""
 
@@ -77,6 +86,59 @@ class DocumentItemOut(BaseModel):
     updated_at: datetime
 
 
+class DocumentItemFullOut(BaseModel):
+    """Document item with its full version history."""
+
+    model_config = ConfigDict(from_attributes=True)
+
+    id: UUID
+    document_id: UUID
+    position: str
+    item_type: str
+    title: str | None = None
+    current_text: str
+    voting_protocol_id: UUID | None = None
+    sort_order: int
+    created_at: datetime
+    updated_at: datetime
+    versions: list[ItemVersionOut] = Field(default_factory=list)
+
+
+class DocumentFullOut(BaseModel):
+    """Document with full items list (not just count)."""
+
+    model_config = ConfigDict(from_attributes=True)
+
+    id: UUID
+    slug: str
+    title: str
+    doc_type: str
+    version: str
+    status: str
+    description: str | None = None
+    ipfs_cid: str | None = None
+    chain_anchor: str | None = None
+    created_at: datetime
+    updated_at: datetime
+    items: list[DocumentItemOut] = Field(default_factory=list)
+
+
+# ── Item Reorder ─────────────────────────────────────────────────
+
+
+class ItemReorderEntry(BaseModel):
+    """A single item reorder entry."""
+
+    item_id: UUID
+    sort_order: int = Field(..., ge=0)
+
+
+class ItemReorderRequest(BaseModel):
+    """Payload for reordering items in a document."""
+
+    items: list[ItemReorderEntry]
+
+
 # ── Item Version ─────────────────────────────────────────────────
 
 
@@ -101,3 +163,11 @@ class ItemVersionOut(BaseModel):
     decision_id: UUID | None = None
     proposed_by_id: UUID | None = None
     created_at: datetime
+
+
+# ── Forward reference resolution ─────────────────────────────────
+# DocumentItemFullOut references ItemVersionOut which is defined after it.
+# With `from __future__ import annotations`, Pydantic needs explicit rebuild.
+
+DocumentItemFullOut.model_rebuild()
+DocumentFullOut.model_rebuild()