Fix program list: show academy-wide programs (null branch_id) alongside branch programs

Programs with branch_id=NULL are academy-wide — they should be visible
regardless of which branch is selected. The filter now uses
WHERE branch_id = X OR branch_id IS NULL.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Livewire/Programs/ProgramList.php

@@ -78,7 +78,9 @@ public function render()
         $query = TrainingProgram::query()
             ->with(['activity', 'branch'])
             ->withCount('groups')
-            ->when($branchId, fn ($q) => $q->where('branch_id', $branchId))
+            ->when($branchId, fn ($q) => $q->where(function ($sub) use ($branchId) {
+                $sub->where('branch_id', $branchId)->orWhereNull('branch_id');
+            }))
             ->when($this->search, fn ($q) => $q->where(function ($sub) {
                 $sub->where('name_ar', 'ilike', "%{$this->search}%")
                     ->orWhere('name', 'ilike', "%{$this->search}%");