feat(web): add lib/phone.ts with formatPhone/normalizePhone/zaloHref helpers

- Create apps/web/lib/phone.ts with VN_PHONE_REGEX, normalizePhone,
  formatPhone, and zaloHref helpers
- Deduplicate phone regex: auth.ts and inquiry.ts now import VN_PHONE_REGEX
  from @/lib/phone instead of defining their own local patterns
- Replace raw .replace(/^0/, '84') in inquiry-detail-dialog.tsx and
  lead-detail-dialog.tsx with zaloHref(); use formatPhone() for display

Resolves GOO-209

Co-Authored-By: Paperclip <noreply@paperclip.ing>

apps/web/components/inquiries/inquiry-detail-dialog.tsx

@@ -13,6 +13,7 @@ import {
 } from '@/components/ui/dialog';
 import { useMarkInquiryRead } from '@/lib/hooks/use-inquiries';
 import type { InquiryReadDto } from '@/lib/inquiries-api';
+import { formatPhone, zaloHref } from '@/lib/phone';
 
 interface InquiryDetailDialogProps {
   inquiry: InquiryReadDto | null;
@@ -42,6 +43,8 @@ export function InquiryDetailDialog({ inquiry, open, onOpenChange }: InquiryDeta
     minute: '2-digit',
   });
 
+  const phone = inquiry.phone ?? inquiry.userPhone;
+
   return (
     <Dialog open={open} onOpenChange={onOpenChange}>
       <DialogContent className="max-w-md sm:max-w-lg">
@@ -60,7 +63,7 @@ export function InquiryDetailDialog({ inquiry, open, onOpenChange }: InquiryDeta
               <InquiryStatusBadge isRead={inquiry.isRead} />
             </div>
             <div className="space-y-1 text-sm text-muted-foreground">
-              <p>SĐT: {inquiry.phone ?? inquiry.userPhone}</p>
+              <p>SĐT: {formatPhone(phone)}</p>
               <p>Ngày gửi: {formattedDate}</p>
             </div>
           </div>
@@ -78,13 +81,13 @@ export function InquiryDetailDialog({ inquiry, open, onOpenChange }: InquiryDeta
             <h4 className="text-sm font-medium">Liên hệ nhanh</h4>
             <div className="flex flex-wrap gap-2">
               <a
-                href={`tel:${inquiry.phone ?? inquiry.userPhone}`}
+                href={`tel:${phone}`}
                 className="inline-flex items-center gap-1.5 rounded-md border px-3 py-1.5 text-sm transition-colors hover:bg-accent"
               >
                 <Phone className="h-4 w-4" aria-hidden="true" /> Gọi điện
               </a>
               <a
-                href={`https://zalo.me/${(inquiry.phone ?? inquiry.userPhone).replace(/^0/, '84')}`}
+                href={zaloHref(phone)}
                 target="_blank"
                 rel="noopener noreferrer"
                 className="inline-flex items-center gap-1.5 rounded-md border px-3 py-1.5 text-sm transition-colors hover:bg-accent"

apps/web/components/leads/lead-detail-dialog.tsx

@@ -15,6 +15,7 @@ import {
 import { Select } from '@/components/ui/select';
 import { useDeleteLead, useUpdateLeadStatus } from '@/lib/hooks/use-leads';
 import { LEAD_STATUSES, LEAD_SOURCES, type LeadReadDto, type LeadStatus } from '@/lib/leads-api';
+import { formatPhone, zaloHref } from '@/lib/phone';
 
 interface LeadDetailDialogProps {
   lead: LeadReadDto | null;
@@ -96,7 +97,7 @@ export function LeadDetailDialog({ lead, open, onOpenChange }: LeadDetailDialogP
               <LeadStatusBadge status={lead.status} />
             </div>
             <div className="space-y-1 text-sm text-muted-foreground">
-              <p>SĐT: {lead.phone}</p>
+              <p>SĐT: {formatPhone(lead.phone)}</p>
               {lead.email && <p>Email: {lead.email}</p>}
               <p>Nguồn: {getSourceLabel(lead.source)}</p>
               {lead.score !== null && <p>Điểm: {lead.score}/100</p>}
@@ -163,7 +164,7 @@ export function LeadDetailDialog({ lead, open, onOpenChange }: LeadDetailDialogP
                 </a>
               )}
               <a
-                href={`https://zalo.me/${lead.phone.replace(/^0/, '84')}`}
+                href={zaloHref(lead.phone)}
                 target="_blank"
                 rel="noopener noreferrer"
                 className="inline-flex items-center gap-1.5 rounded-md border px-3 py-1.5 text-sm transition-colors hover:bg-accent"

apps/web/lib/phone.ts

@@ -0,0 +1,59 @@
+/**
+ * Vietnamese phone number helpers.
+ *
+ * Regex covers the current VN numbering plan:
+ *   0[35789]x xxxxxxx — Viettel, Mobifone, Vinaphone, Gmobile, Indochina
+ *
+ * See: https://en.wikipedia.org/wiki/Telephone_numbers_in_Vietnam
+ */
+
+/** Matches a VN mobile number, with optional +84 or leading 0. */
+export const VN_PHONE_REGEX =
+  /^(0|\+84)(3[2-9]|5[2689]|7[06-9]|8[1-9]|9[0-9])\d{7}$/;
+
+/**
+ * Normalise a VN phone number to the E.164-ish form used by Zalo / APIs:
+ * strip leading 0 and prepend the country code (84).
+ *
+ * "0987654321" → "84987654321"
+ * "+84987654321" → "84987654321"
+ * "84987654321" → "84987654321"  (already normalised — idempotent)
+ */
+export function normalizePhone(phone: string): string {
+  const cleaned = phone.trim();
+  if (cleaned.startsWith('+84')) return `84${cleaned.slice(3)}`;
+  if (cleaned.startsWith('84')) return cleaned;
+  if (cleaned.startsWith('0')) return `84${cleaned.slice(1)}`;
+  return cleaned;
+}
+
+/**
+ * Format a raw VN phone number for display.
+ * Handles 10-digit numbers (0xx xxxx xxxx).
+ *
+ * "0987654321" → "0987 654 321"
+ * Passthrough for anything that doesn't match.
+ */
+export function formatPhone(phone: string): string {
+  const cleaned = phone.trim().replace(/\s+/g, '');
+
+  // 10-digit local format: 0xxx yyy zzz
+  const tenDigit = cleaned.match(/^(0\d{3})(\d{3})(\d{3})$/);
+  if (tenDigit) return `${tenDigit[1]} ${tenDigit[2]} ${tenDigit[3]}`;
+
+  // +84 prefix → treat as 10-digit local after swapping prefix
+  const e164 = cleaned.match(/^\+84(\d{9})$/);
+  if (e164) return formatPhone(`0${e164[1]}`);
+
+  return phone;
+}
+
+/**
+ * Returns the https://zalo.me deep-link URL for a given phone number.
+ *
+ * Zalo expects the number without a leading zero, prefixed with 84.
+ * "0987654321" → "https://zalo.me/84987654321"
+ */
+export function zaloHref(phone: string): string {
+  return `https://zalo.me/${normalizePhone(phone)}`;
+}

apps/web/lib/validations/auth.ts

@@ -1,6 +1,6 @@
 import { z } from 'zod';
 
-const phoneRegex = /^(0|\+84)(3[2-9]|5[2689]|7[06-9]|8[1-9]|9[0-9])\d{7}$/;
+import { VN_PHONE_REGEX as phoneRegex } from '@/lib/phone';
 
 export const loginSchema = z.object({
   phone: z

apps/web/lib/validations/inquiry.ts

@@ -1,12 +1,6 @@
 import { z } from 'zod';
 
-/**
- * Vietnamese phone number rule:
- * - 9–11 digits, optional leading +84 or 0.
- * We keep validation pragmatic: whitespace is stripped, then the remaining
- * string must be 9–11 digits (country code / leading zero stripped).
- */
-const PHONE_REGEX = /^(?:\+?84|0)?\d{9,11}$/;
+import { VN_PHONE_REGEX as PHONE_REGEX } from '@/lib/phone';
 
 export const inquiryFormSchema = z.object({
   message: z