Fix Arvan mail A record value to array of IPs

Arvan CDN 4.0 rejects A creates when value is a single { ip } object
(422: value must be an array). Send [{ ip }] and compare listed A
values as arrays so ensureMailRecords no longer fails before DKIM.

src/arvan-dns/arvan-dns.service.ts

@@ -18,7 +18,8 @@ type ArvanRecordType = 'aname' | 'cname' | 'a' | 'mx' | 'txt';
 type DesiredRecord = {
   type: ArvanRecordType;
   name: string;
-  value: Record<string, unknown>;
+  /** A records use an array of `{ ip }`; other types use a single object. */
+  value: Record<string, unknown> | Array<Record<string, unknown>>;
 };
 
 type DnsMutationResult = {
@@ -34,7 +35,7 @@ type ArvanDnsRecord = {
   name: string;
   ttl?: number;
   cloud?: boolean;
-  value?: Record<string, unknown> | null;
+  value?: Record<string, unknown> | Array<Record<string, unknown>> | null;
 };
 
 @Injectable()
@@ -110,7 +111,8 @@ export class ArvanDnsService {
     await this.upsertTyped(host, auth, existing, {
       type: 'a',
       name: 'mail',
-      value: { ip: MAIL_IPV4 },
+      // Arvan CDN 4.0 requires A `value` as an array of IP objects.
+      value: [{ ip: MAIL_IPV4 }],
     }, created, updated, skipped);
 
     await this.replaceExtraMx(host, auth, existing, removed);
@@ -447,7 +449,7 @@ export class ArvanDnsService {
     const mx = existing.filter((item) => item.type === 'mx');
     const keep = mx.find((item) => {
       const name = this.relativeName(item.name, host);
-      return name === '@' && this.fqdn(this.mxHost(item.value ?? {})) === MAIL_HOSTNAME;
+      return name === '@' && this.fqdn(this.mxHost(this.recordValueObject(item.value))) === MAIL_HOSTNAME;
     });
     for (const item of mx) {
       if (keep && item.id === keep.id) continue;
@@ -462,7 +464,7 @@ export class ArvanDnsService {
         );
       }
       const name = this.relativeName(item.name, host);
-      removed.push(`MX ${name} ${this.mxHost(item.value ?? {}) || item.id}`);
+      removed.push(`MX ${name} ${this.mxHost(this.recordValueObject(item.value)) || item.id}`);
       const index = existing.indexOf(item);
       if (index >= 0) existing.splice(index, 1);
     }
@@ -498,27 +500,51 @@ export class ArvanDnsService {
   }
 
   private sameTarget(desired: DesiredRecord, existing: ArvanDnsRecord): boolean {
-    const current = existing.value ?? {};
+    const current = this.recordValueObject(existing.value);
+    const desiredObj = this.recordValueObject(desired.value);
     if (desired.type === 'aname') {
-      return this.fqdn(String(current.location ?? '')) === this.fqdn(String(desired.value.location ?? ''));
+      return this.fqdn(String(current.location ?? '')) === this.fqdn(String(desiredObj.location ?? ''));
     }
     if (desired.type === 'a') {
-      return String(current.ip ?? '') === String(desired.value.ip ?? '');
+      return this.aIps(existing.value).join(',') === this.aIps(desired.value).join(',');
     }
     if (desired.type === 'mx') {
       return (
-        this.fqdn(this.mxHost(current)) === this.fqdn(String(desired.value.host ?? '')) &&
-        Number(current.priority ?? 0) === Number(desired.value.priority ?? 0)
+        this.fqdn(this.mxHost(current)) === this.fqdn(String(desiredObj.host ?? '')) &&
+        Number(current.priority ?? 0) === Number(desiredObj.priority ?? 0)
       );
     }
     if (desired.type === 'txt') {
-      return this.txtValue(existing).replace(/\s+/g, '') === String(desired.value.text ?? '').replace(/\s+/g, '');
+      return this.txtValue(existing).replace(/\s+/g, '') === String(desiredObj.text ?? '').replace(/\s+/g, '');
     }
-    return this.fqdn(String(current.host ?? '')) === this.fqdn(String(desired.value.host ?? ''));
+    return this.fqdn(String(current.host ?? '')) === this.fqdn(String(desiredObj.host ?? ''));
+  }
+
+  /** Arvan A records return `value` as `[{ ip }]`; normalize to IP list for compare/send. */
+  private aIps(value: DesiredRecord['value'] | ArvanDnsRecord['value']): string[] {
+    if (Array.isArray(value)) {
+      return value
+        .map((item) => String(item?.ip ?? '').trim())
+        .filter(Boolean);
+    }
+    if (value && typeof value === 'object' && 'ip' in value) {
+      const ip = String(value.ip ?? '').trim();
+      return ip ? [ip] : [];
+    }
+    return [];
+  }
+
+  private recordValueObject(
+    value: DesiredRecord['value'] | ArvanDnsRecord['value'],
+  ): Record<string, unknown> {
+    if (Array.isArray(value)) {
+      return (value[0] as Record<string, unknown> | undefined) ?? {};
+    }
+    return value ?? {};
   }
 
   private txtValue(record: ArvanDnsRecord): string {
-    const value = record.value ?? {};
+    const value = this.recordValueObject(record.value);
     if (typeof value.text === 'string') return value.text;
     if (value.txt && typeof value.txt === 'object' && 'text' in value.txt) {
       return String((value.txt as { text?: unknown }).text ?? '');