fix(models): replace forceFill/forceCreate with fill/create and add fillable guards

Replace all uses of `forceFill`, `forceCreate`, and `forceFill` with their
non-force equivalents across models, actions, controllers, and Livewire
components. Add explicit `$fillable` arrays to all affected Eloquent models
to enforce mass assignment protection.

Add ModelFillableCreationTest and ModelFillableRegressionTest to verify that
model creation respects fillable constraints and prevent regressions.

app/Livewire/Boarding/Index.php

@@ -441,7 +441,7 @@ class Index extends Component
 
     public function createNewProject()
     {
-        $this->createdProject = Project::forceCreate([
+        $this->createdProject = Project::create([
             'name' => 'My first project',
             'team_id' => currentTeam()->id,
             'uuid' => (string) new Cuid2,