fix(ipintelligence): handle flat geolocation MMDB schema and clean up DNS client lifecycle

ts/smartnetwork.classes.ipintelligence.ts

@@ -2,7 +2,21 @@ import * as plugins from './smartnetwork.plugins.js';
 import { getLogger } from './logging.js';
 
 // MaxMind types re-exported from mmdb-lib via maxmind
-import type { CityResponse, AsnResponse, Reader } from 'maxmind';
+import type { AsnResponse, Reader, Response } from 'maxmind';
+
+/**
+ * The @ip-location-db MMDB files use a flat schema instead of the standard MaxMind nested format.
+ */
+interface IIpLocationDbCityRecord {
+  city?: string;
+  country_code?: string;
+  latitude?: number;
+  longitude?: number;
+  postcode?: string;
+  state1?: string;
+  state2?: string;
+  timezone?: string;
+}
 
 /**
  * Unified result from all IP intelligence layers
@@ -70,7 +84,7 @@ export class IpIntelligence {
   private readonly timeout: number;
 
   // MaxMind readers (lazily initialized)
-  private cityReader: Reader<CityResponse> | null = null;
+  private cityReader: Reader<IIpLocationDbCityRecord & Response> | null = null;
   private asnReader: Reader<AsnResponse> | null = null;
   private lastFetchTime = 0;
   private refreshPromise: Promise<void> | null = null;
@@ -371,11 +385,12 @@ export class IpIntelligence {
    * Response: "ASN | prefix | CC | rir | date"
    */
   private async queryTeamCymru(ip: string): Promise<{ asn: number; prefix: string; country: string } | null> {
+    let dnsClient: InstanceType<typeof plugins.smartdns.dnsClientMod.Smartdns> | null = null;
     try {
       const reversed = ip.split('.').reverse().join('.');
       const queryName = `${reversed}.origin.asn.cymru.com`;
 
-      const dnsClient = new plugins.smartdns.dnsClientMod.Smartdns({
+      dnsClient = new plugins.smartdns.dnsClientMod.Smartdns({
         strategy: 'prefer-system',
         allowDohFallback: true,
         timeoutMs: this.timeout,
@@ -402,6 +417,10 @@ export class IpIntelligence {
     } catch (err: any) {
       this.logger.debug?.(`Team Cymru DNS query failed for ${ip}: ${err.message}`);
       return null;
+    } finally {
+      if (dnsClient) {
+        dnsClient.destroy();
+      }
     }
   }
 
@@ -442,7 +461,7 @@ export class IpIntelligence {
       this.fetchBuffer(ASN_MMDB_URL),
     ]);
 
-    this.cityReader = new plugins.maxmind.Reader<CityResponse>(cityBuffer);
+    this.cityReader = new plugins.maxmind.Reader<IIpLocationDbCityRecord & Response>(cityBuffer);
     this.asnReader = new plugins.maxmind.Reader<AsnResponse>(asnBuffer);
     this.lastFetchTime = Date.now();
     this.logger.info?.('MaxMind MMDB databases loaded into memory');
@@ -495,17 +514,17 @@ export class IpIntelligence {
     let asn: number | null = null;
     let asnOrg: string | null = null;
 
-    // City lookup
+    // City lookup — @ip-location-db uses flat schema: city, country_code, latitude, longitude, etc.
     try {
       const cityResult = this.cityReader.get(ip);
       if (cityResult) {
-        country = cityResult.country?.names?.en || null;
-        countryCode = cityResult.country?.iso_code || null;
-        city = cityResult.city?.names?.en || null;
-        latitude = cityResult.location?.latitude ?? null;
-        longitude = cityResult.location?.longitude ?? null;
-        accuracyRadius = cityResult.location?.accuracy_radius ?? null;
-        timezone = cityResult.location?.time_zone || null;
+        countryCode = cityResult.country_code || null;
+        city = cityResult.city || null;
+        latitude = cityResult.latitude ?? null;
+        longitude = cityResult.longitude ?? null;
+        timezone = cityResult.timezone || null;
+        // @ip-location-db does not include country name or accuracy_radius
+        // We leave country null (countryCode is available)
       }
     } catch (err: any) {
       this.logger.debug?.(`MaxMind city lookup failed for ${ip}: ${err.message}`);