Fusionne dev dans feat/stats-summary

Resout les conflits de deps.py, router.py, repositories/site.py et
test_site.py entre l'ajout de stats et le merge de sites/openapi-contrat
sur dev. Generalise ROUTES_A_ROLE dans test_openapi.py et documente la
checklist d'ajout d'une route metier, absentes de dev au moment du fork.

apps/backend/tests/services/test_site.py

@@ -0,0 +1,49 @@
+import pytest
+
+from app.models.energy import Site
+from app.services.site import SiteNotFoundError, SiteService
+
+
+def site(site_id: str = "site-1") -> Site:
+    return Site(
+        site_id=site_id,
+        site_name="Site de test",
+        site_type="industriel",
+        location="Toulouse",
+        capacity_kw=42.0,
+        status="actif",
+    )
+
+
+class FakeRepository:
+    def __init__(self, sites: list[Site]) -> None:
+        self._sites = sites
+
+    async def list_all(self) -> list[Site]:
+        return self._sites
+
+    async def get_by_id(self, site_id: str) -> Site | None:
+        return next((s for s in self._sites if s.site_id == site_id), None)
+
+
+async def test_list_all_returns_the_repository_sites() -> None:
+    service = SiteService(sites=FakeRepository([site("a"), site("b")]))
+
+    sites = await service.list_all()
+
+    assert [s.site_id for s in sites] == ["a", "b"]
+
+
+async def test_get_by_id_returns_the_matching_site() -> None:
+    service = SiteService(sites=FakeRepository([site("a")]))
+
+    trouve = await service.get_by_id("a")
+
+    assert trouve.site_id == "a"
+
+
+async def test_get_by_id_raises_when_the_site_is_unknown() -> None:
+    service = SiteService(sites=FakeRepository([]))
+
+    with pytest.raises(SiteNotFoundError):
+        await service.get_by_id("inconnu")