refactor(project-management) : introduce Project/Task/TaskTag/Client contracts

Tranche 1 of LST-65 (ProjectManagement module migration). Decouples the
TimeTracking module from the core-business entities before they move, with
no entity relocation yet — keeps the diff minimal and the risk isolated.

- New read contracts in Shared/Domain/Contract (minimal surface, aligned on
  the entities' real nullable signatures): ProjectInterface (id/code/name),
  TaskInterface (id/number/title), TaskTagInterface (id/label/color),
  ClientInterface (id/name).
- Project/Task/TaskTag/Client implement their contract (entities stay in
  src/Entity for now). Project.client typed as ClientInterface.
- TimeEntry (TimeTracking) now references ProjectInterface/TaskInterface/
  TaskTagInterface instead of the concrete entities; repository + DQL
  untouched in behaviour.
- resolve_target_entities maps the 4 contracts to the legacy entities (will
  be repointed to the module in tranche 2).
- Adds the migration plan doc.

159 tests green, mapping valid, cs-fixer clean.

src/Entity/Client.php

@@ -11,6 +11,7 @@ use ApiPlatform\Metadata\GetCollection;
 use ApiPlatform\Metadata\Patch;
 use ApiPlatform\Metadata\Post;
 use App\Repository\ClientRepository;
+use App\Shared\Domain\Contract\ClientInterface;
 use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\Common\Collections\Collection;
 use Doctrine\ORM\Mapping as ORM;
@@ -29,7 +30,7 @@ use Symfony\Component\Serializer\Attribute\Groups;
     order: ['name' => 'ASC'],
 )]
 #[ORM\Entity(repositoryClass: ClientRepository::class)]
-class Client
+class Client implements ClientInterface
 {
     #[ORM\Id]
     #[ORM\GeneratedValue]

src/Entity/Project.php

@@ -15,6 +15,8 @@ use ApiPlatform\Metadata\Patch;
 use ApiPlatform\Metadata\Post;
 use App\ApiResource\SwitchWorkflowOutput;
 use App\Repository\ProjectRepository;
+use App\Shared\Domain\Contract\ClientInterface;
+use App\Shared\Domain\Contract\ProjectInterface;
 use App\State\SwitchProjectWorkflowProcessor;
 use Doctrine\Common\Collections\ArrayCollection;
 use Doctrine\Common\Collections\Collection;
@@ -54,7 +56,7 @@ use Symfony\Component\Validator\Constraints as Assert;
 #[ApiFilter(BooleanFilter::class, properties: ['archived'])]
 #[ORM\Entity(repositoryClass: ProjectRepository::class)]
 #[UniqueEntity(fields: ['code'], message: 'Ce code de projet est déjà utilisé.')]
-class Project
+class Project implements ProjectInterface
 {
     #[ORM\Id]
     #[ORM\GeneratedValue]
@@ -80,10 +82,10 @@ class Project
     #[Groups(['project:read', 'project:write', 'time_entry:read', 'task:read'])]
     private ?string $color = '#222783';
 
-    #[ORM\ManyToOne(targetEntity: Client::class, inversedBy: 'projects')]
+    #[ORM\ManyToOne(targetEntity: ClientInterface::class, inversedBy: 'projects')]
     #[ORM\JoinColumn(nullable: true, onDelete: 'SET NULL')]
     #[Groups(['project:read', 'project:write'])]
-    private ?Client $client = null;
+    private ?ClientInterface $client = null;
 
     #[ORM\ManyToOne(targetEntity: Workflow::class)]
     #[ORM\JoinColumn(nullable: false, onDelete: 'RESTRICT')]
@@ -173,12 +175,12 @@ class Project
         return $this;
     }
 
-    public function getClient(): ?Client
+    public function getClient(): ?ClientInterface
     {
         return $this->client;
     }
 
-    public function setClient(?Client $client): static
+    public function setClient(?ClientInterface $client): static
     {
         $this->client = $client;
 

src/Entity/Task.php

@@ -16,6 +16,7 @@ use ApiPlatform\Metadata\GetCollection;
 use ApiPlatform\Metadata\Patch;
 use ApiPlatform\Metadata\Post;
 use App\Repository\TaskRepository;
+use App\Shared\Domain\Contract\TaskInterface;
 use App\Shared\Domain\Contract\UserInterface;
 use App\State\TaskCalendarProcessor;
 use App\State\TaskNumberProcessor;
@@ -46,7 +47,7 @@ use Symfony\Component\Validator\Context\ExecutionContextInterface;
 #[ORM\Entity(repositoryClass: TaskRepository::class)]
 #[ORM\Table(name: 'task')]
 #[ORM\UniqueConstraint(name: 'uniq_task_project_number', columns: ['project_id', 'number'])]
-class Task
+class Task implements TaskInterface
 {
     #[ORM\Id]
     #[ORM\GeneratedValue]

src/Entity/TaskTag.php

@@ -11,6 +11,7 @@ use ApiPlatform\Metadata\GetCollection;
 use ApiPlatform\Metadata\Patch;
 use ApiPlatform\Metadata\Post;
 use App\Repository\TaskTagRepository;
+use App\Shared\Domain\Contract\TaskTagInterface;
 use Doctrine\ORM\Mapping as ORM;
 use Symfony\Component\Serializer\Attribute\Groups;
 
@@ -28,7 +29,7 @@ use Symfony\Component\Serializer\Attribute\Groups;
 )]
 #[ORM\Entity(repositoryClass: TaskTagRepository::class)]
 #[ORM\Table(name: 'task_type')]
-class TaskTag
+class TaskTag implements TaskTagInterface
 {
     #[ORM\Id]
     #[ORM\GeneratedValue]