feat(security): 新增网站安全扩展模块并支持修改手机脱敏验证

inc/helpers/aksrt-phone.php

@@ -0,0 +1,68 @@
+<?php
+/**
+ * Phone number masking helpers shared by the account UI and the
+ * phone-match verification endpoint.
+ *
+ * The hidden middle segment adapts to the number: domestic 11-digit
+ * numbers hide 4 digits (138****1234), longer international numbers
+ * hide length-7 digits (min 4), so the digit-entry UI renders one box
+ * per hidden digit.
+ *
+ * @package AKSRT
+ */
+
+if (!defined('ABSPATH')) {
+	exit;
+}
+
+/**
+ * Split a bound phone number into visible prefix / hidden middle / visible suffix.
+ *
+ * Works on the digit core of the number (a leading "+" is ignored for the split
+ * but reported back). Returns null when the number holds fewer than 8 digits —
+ * such numbers cannot be verified by middle-digit entry.
+ *
+ * @return array{prefix:string,hidden:string,suffix:string,hidden_length:int,leading_plus:bool}|null
+ */
+function aksrt_phone_mask_parts(string $phone): ?array {
+	$phone = trim($phone);
+	if ($phone === '') {
+		return null;
+	}
+
+	$leading_plus = $phone[0] === '+';
+	$core = preg_replace('/\D+/', '', $phone);
+	$length = strlen($core);
+	if ($length < 8) {
+		return null;
+	}
+
+	$hidden_length = min(11, max(4, $length - 7));
+	$suffix_length = $length - 3 - $hidden_length;
+	if ($suffix_length < 1) {
+		return null;
+	}
+
+	return [
+		'prefix'        => substr($core, 0, 3),
+		'hidden'        => substr($core, 3, $hidden_length),
+		'suffix'        => substr($core, $length - $suffix_length),
+		'hidden_length' => $hidden_length,
+		'leading_plus'  => $leading_plus,
+	];
+}
+
+/**
+ * Masked display form of a phone number, e.g. 138****1234 or +861******1234.
+ * Falls back to the raw number when it cannot be masked.
+ */
+function aksrt_phone_mask_display(string $phone): string {
+	$parts = aksrt_phone_mask_parts($phone);
+	if ($parts === null) {
+		return $phone;
+	}
+
+	$mask = str_repeat('*', (int) $parts['hidden_length']);
+	$display = $parts['prefix'] . $mask . $parts['suffix'];
+	return $parts['leading_plus'] ? '+' . $display : $display;
+}