chore(lint): trier les imports, sauf la facade des modeles

Active la regle isort (I) de ruff. 45 fichiers reordonnes, aucun
changement de comportement : la suite passe avant comme apres.

app/models/__init__.py en est exclu. Ses imports sont ranges en onze
couches commentees qui decrivent le graphe de dependances ; trier par
ordre alphabetique laisse chaque titre au-dessus d un import qu il ne
decrit pas, et ce fichier n a qu un role, etre lu.

Commit isole, comme le formatage : un diff de brassage ne doit pas
servir de couverture a un changement de comportement.

app/models/user_model/__init__.py

@@ -1,10 +1,10 @@
 """User hierarchy — single-table polymorphic inheritance (User → Admin, Manager, Coach, Player, Scout)."""
 
-from app.models.user_model.user import User
 from app.models.user_model.admin import Admin
-from app.models.user_model.manager import Manager
 from app.models.user_model.coach import Coach
+from app.models.user_model.manager import Manager
 from app.models.user_model.player import Player
 from app.models.user_model.scout import Scout
+from app.models.user_model.user import User
 
 __all__ = ['User', 'Admin', 'Manager', 'Coach', 'Player', 'Scout']

app/models/user_model/manager.py

@@ -27,9 +27,10 @@ class Manager(User):
         return True
 
     def get_visible_tryouts(self):
-        from app.models.tryout.tryout import Tryout
         from sqlalchemy import or_
 
+        from app.models.tryout.tryout import Tryout
+
         return (
             Tryout.query.filter(or_(Tryout.created_by == self.id, Tryout.manager_id == self.id))
             .order_by(Tryout.date)

app/models/user_model/player.py

@@ -9,9 +9,9 @@ class Player(User):
     __mapper_args__ = {'polymorphic_identity': 'player'}
 
     def get_visible_tryouts(self):
-        from app.models.tryout.tryout import Tryout
         from app.models.match_model.match import Match
         from app.models.participant.match_participant import MatchParticipant
+        from app.models.tryout.tryout import Tryout
 
         # tryouts they registered for
         player_tryout_ids = [r.tryout_id for r in self.tryout_registrations.all()]

app/models/user_model/user.py

@@ -1,9 +1,11 @@
 """Base User model — shared fields and polymorphic configuration."""
 
-from app.extensions import db
-from flask_login import UserMixin
 from datetime import datetime
 
+from flask_login import UserMixin
+
+from app.extensions import db
+
 
 class User(UserMixin, db.Model):
     """Base user model — shared fields for every role.