Fix semester context, attendance rosters, and billing workflows

- load global semester helpers consistently and use date-based semester defaults
- fix grading and daily attendance duplicate student/section rows
- keep attendance violations scoped to the current semester by default
- update invoice, refund, discount, payment, and financial aid flows
- add configuration cleanup migrations for duplicate calendar/semester keys
- refresh parent registration/report-card and print request handling
- update related models, services, views, cron notes, and test coverage

app/Libraries/InvoiceIssuanceService.php

@@ -27,6 +27,12 @@ class InvoiceIssuanceService
     public function issueInvoice(IssueInvoiceCommand $command): InvoiceLedgerResult
     {
         $invoiceData = $command->invoiceData;
+        if (trim((string)($invoiceData['invoice_number'] ?? '')) === '') {
+            $invoiceData['invoice_number'] = $this->generateInvoiceNumber(
+                (string)($invoiceData['school_year'] ?? ''),
+                (int)($invoiceData['parent_id'] ?? 0)
+            );
+        }
         $invoiceData['status'] = FinancialStatus::INVOICE_DRAFT;
         $invoiceData['total_amount'] = $invoiceData['total_amount'] ?? number_format($command->tuitionAmount + $command->eventAmount, 2, '.', '');
         $invoiceData['balance'] = $invoiceData['balance'] ?? $invoiceData['total_amount'];
@@ -78,6 +84,54 @@ class InvoiceIssuanceService
         }
     }
 
+    public function generateInvoiceNumber(string $schoolYear, ?int $parentId = null): string
+    {
+        $prefix = $this->invoiceNumberPrefix($schoolYear, $parentId);
+        do {
+            $invoiceNumber = $prefix . '-' . uniqid();
+            $exists = $this->db->table('invoices')
+                ->where('invoice_number', $invoiceNumber)
+                ->countAllResults() > 0;
+        } while ($exists);
+
+        return $invoiceNumber;
+    }
+
+    private function invoiceNumberPrefix(string $schoolYear, ?int $parentId = null): string
+    {
+        $year = date('y');
+        if (preg_match('/^(\d{4})-\d{4}$/', $schoolYear, $matches) === 1) {
+            $year = substr($matches[1], -2);
+        }
+
+        $parentSuffix = $this->parentSchoolIdSuffix((int)($parentId ?? 0));
+        if ($parentSuffix !== '') {
+            return 'INV-' . $year . $parentSuffix;
+        }
+
+        return 'INV-' . $year . str_pad((string) max(0, (int)($parentId ?? 0)), 5, '0', STR_PAD_LEFT);
+    }
+
+    private function parentSchoolIdSuffix(int $parentId): string
+    {
+        if ($parentId <= 0) {
+            return '';
+        }
+
+        $row = $this->db->table('users')
+            ->select('school_id')
+            ->where('id', $parentId)
+            ->get()
+            ->getRowArray();
+
+        $schoolId = trim((string)($row['school_id'] ?? ''));
+        if (preg_match('/^\d{2}(\d{5})$/', $schoolId, $matches) === 1) {
+            return $matches[1];
+        }
+
+        return '';
+    }
+
     private function requireWrite($result, string $code, $model = null): void
     {
         if ($result === false || $result === null || $result === 0) {