fix(transfers): child separation gives NEW number, parent keeps theirs

Child separation is not a death/full transfer — the parent stays active
with their original membership number. The separated child gets a brand
new sequential number via MemberNumberGenerator::getNextMembershipNumber().

Only full_transfer type archives the source member and passes the same
number to the new member.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Modules/Transfers/Services/TransferProcessor.php

@@ -79,8 +79,6 @@ final class TransferProcessor
                 $recipientData = $notesDecoded['recipient_data'] ?? [];
             }
 
-            $sameNumber = $sourceMember['membership_number'];
-
             // Find the separation_fee payment that was made for this transfer
             $transferPayment = $db->selectOne(
                 "SELECT id FROM payments WHERE member_id = ? AND payment_type = 'separation_fee' AND related_entity_type = 'transfer_requests' AND related_entity_id = ? AND is_voided = 0 ORDER BY id DESC LIMIT 1",
@@ -88,25 +86,35 @@ final class TransferProcessor
             );
             $transferPaymentId = $transferPayment ? (int) $transferPayment['id'] : null;
 
-            // 3. Archive source member FIRST — releases the unique membership_number
-            $db->update('members', [
-                'membership_number' => null,
-                'status'            => 'transferred',
-                'is_archived'       => 1,
-                'archived_at'       => date('Y-m-d H:i:s'),
-                'updated_at'        => date('Y-m-d H:i:s'),
-            ], '`id` = ?', [(int) $sourceMember['id']]);
-
-            // Verify number is actually released (no other member holds it)
-            $numberConflict = $db->selectOne(
-                "SELECT id FROM members WHERE membership_number = ? AND id != ?",
-                [$sameNumber, (int) $sourceMember['id']]
-            );
-            if ($numberConflict) {
-                $sameNumber = MemberNumberGenerator::generateNext();
+            // 3. Determine membership number for new member
+            $isChildSeparation = ($request['transfer_type'] === 'child_separation');
+            $newNumber = null;
+
+            if ($isChildSeparation) {
+                // Child separation: parent KEEPS their number, child gets a NEW number
+                $newNumber = (string) MemberNumberGenerator::getNextMembershipNumber();
+            } else {
+                // Full transfer / death: archive source, new member inherits SAME number
+                $newNumber = $sourceMember['membership_number'];
+                $db->update('members', [
+                    'membership_number' => null,
+                    'status'            => 'transferred',
+                    'is_archived'       => 1,
+                    'archived_at'       => date('Y-m-d H:i:s'),
+                    'updated_at'        => date('Y-m-d H:i:s'),
+                ], '`id` = ?', [(int) $sourceMember['id']]);
+
+                // Verify number is actually released
+                $numberConflict = $db->selectOne(
+                    "SELECT id FROM members WHERE membership_number = ? AND id != ?",
+                    [$newNumber, (int) $sourceMember['id']]
+                );
+                if ($numberConflict) {
+                    $newNumber = MemberNumberGenerator::generateNext();
+                }
             }
 
-            // 4. Create new member record with SAME membership number
+            // 4. Create new member record
             // Derive date_of_birth and gender from national_id if not directly available
             $dob = $recipientData['date_of_birth'] ?? $subjectData['date_of_birth'] ?? null;
             $gender = $recipientData['gender'] ?? $subjectData['gender'] ?? null;
@@ -153,7 +161,7 @@ final class TransferProcessor
                 'qualification_id'       => $recipientData['qualification_id'] ?? $subjectData['qualification_id'] ?? $sourceMember['qualification_id'],
                 'phone_mobile'           => $phoneMobile,
                 'membership_value'       => $request['new_membership_value'],
-                'membership_number'      => $sameNumber,
+                'membership_number'      => $newNumber,
                 'created_at'             => date('Y-m-d H:i:s'),
                 'updated_at'             => date('Y-m-d H:i:s'),
                 'created_by'             => $employee ? (int) $employee->id : null,
@@ -171,7 +179,7 @@ final class TransferProcessor
 
             // 5. Record number chain
             ArchiveService::recordNumberTransfer(
-                $sameNumber,
+                $newNumber,
                 $request['transfer_type'],
                 'members',
                 $newMemberId,
@@ -335,7 +343,7 @@ final class TransferProcessor
             // 7. Mark transfer request complete
             $db->update('transfer_requests', [
                 'target_member_id'     => $newMemberId,
-                'new_membership_number'=> $sameNumber,
+                'new_membership_number'=> $newNumber,
                 'archive_snapshot_id'  => $snapshotId,
                 'completed_at'         => date('Y-m-d H:i:s'),
                 'status'               => 'completed',
@@ -349,7 +357,7 @@ final class TransferProcessor
                 'transfer_id'      => $transferRequestId,
                 'source_member_id' => (int) $request['source_member_id'],
                 'target_member_id' => $newMemberId,
-                'new_number'       => $sameNumber,
+                'new_number'       => $newNumber,
                 'transfer_type'    => $request['transfer_type'],
                 'fee_amount'       => $request['total_fee'] ?? $request['separation_fee'] ?? '0.00',
                 'old_number'       => $sourceMember['membership_number'] ?? null,
@@ -358,13 +366,13 @@ final class TransferProcessor
             Logger::info("Transfer completed", [
                 'transfer_id' => $transferRequestId,
                 'new_member'  => $newMemberId,
-                'new_number'  => $sameNumber,
+                'new_number'  => $newNumber,
             ]);
 
             return [
                 'success'          => true,
                 'new_member_id'    => $newMemberId,
-                'new_number'       => $sameNumber,
+                'new_number'       => $newNumber,
                 'snapshot_id'      => $snapshotId,
                 'transfer_id'      => $transferRequestId,
             ];