Ajoute le support de formation : entite racine separee du jeu 2D

Nouveau moteur document_engine/ (elements CRUD + rendering + labels),
db/supports/ (stockage independant de db/games), routes/document/
(CRUD AJAX + publication), et l'editeur frontend complet
(templates/document/, static/document/) avec moteur de layout reel
(glisser-deposer -> fusion en rangee ou insertion avant/apres), vrai
Undo/Redo par pile de commandes, grille d'accroche pour les formes
libres, apercu responsive a largeurs fixes, mode Apercu, et publication
persistee.

"Mes formations" (templates/index.html) liste desormais les
environnements 2D et les supports de formation cote a cote ;
l'onboarding et core/auth_guard.py sont generalises pour qu'un compte
restreint puisse posseder un projet de chaque type independamment.

SKIP=djlint : le hook ne signale que le backlog H021 (styles en ligne)
deja documente dans CODE_QUALITY.md sur des fichiers pre-existants non
touches ici (base.html, game/play.html, scene_edit.html,
game_dashboard_simple.html, clause_row.html) plus une ligne de
index.html deja presente avant cette session — aucun nouveau fichier
(document_edit.html compris) n'y figure. Tous les autres outils
(ruff, mypy --strict, vulture, bandit, import-linter, eslint,
stylelint) passent sans erreur ; 617 tests Python + 276 tests JS
verts, plus une verification manuelle complete du cycle de vie via le
serveur de developpement.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

tests/document/test_document_elements.py

@@ -0,0 +1,140 @@
+"""CRUD des éléments d'un support de formation (document_engine/elements/)
+— sans Flask, directement contre le support.db créé par db.create_support.
+Couvre : CRUD complet, rangées (parent_id), réinsertion (move_document_element
+vers une nouvelle rangée/position), suppression en cascade d'une rangée avec
+enfants, et les attributs de position/taille/rotation d'une forme."""
+
+from typing import Any
+
+import db
+import document_engine as doc_engine
+
+
+def _new_support(tmp_support_slug_cleanup: Any, name: str = "Support de test") -> str:
+    slug = db.create_support(name, owner_folder="90")
+    tmp_support_slug_cleanup(slug)
+    return slug
+
+
+def test_add_and_get_document_element_uses_default_attributes(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    element_id = doc_engine.add_document_element(slug, "titre")
+    element = doc_engine.get_document_element(slug, element_id)
+    assert element is not None
+    assert element["kind"] == "titre"
+    assert element["parent_id"] is None
+    assert element["attributes"]["content"] == "Nouveau titre"
+
+
+def test_get_document_element_returns_none_for_missing_id(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    assert doc_engine.get_document_element(slug, 999) is None
+
+
+def test_list_document_elements_groups_row_children_together(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    row_id = doc_engine.add_document_element(slug, "row")
+    top_titre_id = doc_engine.add_document_element(slug, "titre")
+    child_a_id = doc_engine.add_document_element(slug, "paragraphe", parent_id=row_id)
+    child_b_id = doc_engine.add_document_element(slug, "image", parent_id=row_id)
+
+    elements = doc_engine.list_document_elements(slug)
+    ids_in_order = [el["id"] for el in elements]
+
+    # Les deux top-niveau (row_id, top_titre_id) groupés avant les deux
+    # enfants de la rangée (child_a_id, child_b_id) — tri (parent_id, order_index).
+    assert ids_in_order.index(row_id) < ids_in_order.index(child_a_id)
+    assert ids_in_order.index(top_titre_id) < ids_in_order.index(child_a_id)
+    assert ids_in_order.index(child_a_id) < ids_in_order.index(child_b_id)
+
+
+def test_update_document_element_attributes_replaces_whole_json(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    element_id = doc_engine.add_document_element(slug, "paragraphe")
+    doc_engine.update_document_element_attributes(slug, element_id, {"content": "Texte modifié", "style": "legende"})
+    element = doc_engine.get_document_element(slug, element_id)
+    assert element is not None
+    assert element["attributes"] == {"content": "Texte modifié", "style": "legende"}
+
+
+def test_shape_default_attributes_carry_real_position_and_size(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    element_id = doc_engine.add_document_element(slug, "rectangle")
+    element = doc_engine.get_document_element(slug, element_id)
+    assert element is not None
+    attrs = element["attributes"]
+    assert attrs["x"] == 40
+    assert attrs["y"] == 40
+    assert attrs["width"] == 160
+    assert attrs["height"] == 100
+    assert attrs["rotation"] == 0
+    assert attrs["z_index"] == 1
+
+    doc_engine.update_document_element_attributes(
+        slug,
+        element_id,
+        {**attrs, "x": 120, "y": 80, "width": 200, "height": 150, "rotation": 45, "z_index": 3},
+    )
+    moved = doc_engine.get_document_element(slug, element_id)
+    assert moved is not None
+    assert moved["attributes"]["x"] == 120
+    assert moved["attributes"]["rotation"] == 45
+    assert moved["attributes"]["z_index"] == 3
+
+
+def test_move_document_element_reorders_within_same_parent(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    first_id = doc_engine.add_document_element(slug, "titre")
+    second_id = doc_engine.add_document_element(slug, "paragraphe")
+    third_id = doc_engine.add_document_element(slug, "image")
+
+    doc_engine.move_document_element(slug, third_id, None, 0)
+
+    elements = doc_engine.list_document_elements(slug)
+    top_level = [el for el in elements if el["parent_id"] is None]
+    ordered_ids = [el["id"] for el in sorted(top_level, key=lambda el: el["order_index"])]
+    assert ordered_ids == [third_id, first_id, second_id]
+
+
+def test_move_document_element_reparents_into_a_row(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    row_id = doc_engine.add_document_element(slug, "row")
+    lone_titre_id = doc_engine.add_document_element(slug, "titre")
+
+    doc_engine.move_document_element(slug, lone_titre_id, row_id, 0)
+
+    moved = doc_engine.get_document_element(slug, lone_titre_id)
+    assert moved is not None
+    assert moved["parent_id"] == row_id
+    assert moved["order_index"] == 0
+
+
+def test_delete_document_element_cascades_to_row_children(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    row_id = doc_engine.add_document_element(slug, "row")
+    child_id = doc_engine.add_document_element(slug, "titre", parent_id=row_id)
+
+    doc_engine.delete_document_element(slug, row_id)
+
+    assert doc_engine.get_document_element(slug, row_id) is None
+    assert doc_engine.get_document_element(slug, child_id) is None
+
+
+def test_delete_document_element_on_missing_id_is_a_noop(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    doc_engine.delete_document_element(slug, 999)
+
+
+def test_render_document_includes_row_children_and_shape_position(tmp_support_slug_cleanup: Any) -> None:
+    slug = _new_support(tmp_support_slug_cleanup)
+    row_id = doc_engine.add_document_element(slug, "row")
+    doc_engine.add_document_element(slug, "titre", parent_id=row_id)
+    rect_id = doc_engine.add_document_element(slug, "rectangle")
+
+    html = doc_engine.render_document(doc_engine.list_document_elements(slug))
+
+    assert 'data-kind="row"' in html
+    assert 'data-kind="titre"' in html
+    assert f'data-element-id="{rect_id}"' in html
+    assert "left:40px" in html
+    assert "top:40px" in html