feat(geo): support overriding Nominatim endpoint via env

server/src/app-config/README.md

@@ -82,7 +82,7 @@ TREK_PLUGINS_ENABLED / _DEV_LINK / _IGNORE_TREK_RANGE / _DIR / _DATA_DIR / TREK_
 OIDC_*, SMTP_*, FORCE_HTTPS, COOKIE_SECURE, HSTS_INCLUDE_SUBDOMAINS,
 ALLOWED_ORIGINS, UNSPLASH_ACCESS_KEY, WEBAUTHN_*, TZ, ADMIN_EMAIL,
 ADMIN_PASSWORD, IDEMPOTENCY_TTL_SECONDS, MCP_RATE_LIMIT (request-path check),
-LLM_TIMEOUT_MS.
+LLM_TIMEOUT_MS, NOMINATIM_URL.
 
 ## Exemptions — raw `process.env` stays
 

server/src/app-config/derive.ts

@@ -265,6 +265,7 @@ export function deriveIntegrations(raw: RawEnv) {
   return {
     unsplashAccessKey: raw.UNSPLASH_ACCESS_KEY?.trim(),
     transitApiBase: stripTrailingSlashes(raw.TRANSIT_API_URL || 'https://api.transitous.org'),
+    nominatimUrl: stripTrailingSlashes(raw.NOMINATIM_URL || 'https://nominatim.openstreetmap.org'),
     overpassUrl: raw.OVERPASS_URL,
     // Longer than the `[timeout:20]` the query itself carries, or we abort an answer the
     // mirror was still allowed to be working on. See OVERPASS_QUERY_TIMEOUT_S.

server/src/app-config/env.schema.ts

@@ -108,6 +108,7 @@ export const envSchema = z.object({
   // Integrations
   UNSPLASH_ACCESS_KEY: anyString,
   TRANSIT_API_URL: url,
+  NOMINATIM_URL: url,
   // OVERPASS_URL accepts a comma-separated endpoint list and silently drops
   // non-http(s) entries today — left unvalidated to keep that behavior.
   OVERPASS_URL: anyString,

server/src/nest/geo/nominatim.client.ts

@@ -1,4 +1,5 @@
 import { UA } from '../maps/maps.helpers';
+import { readEnv } from '../../app-config';
 
 /**
  * The one Nominatim client.
@@ -21,7 +22,6 @@ import { UA } from '../maps/maps.helpers';
  * header, not the weaker one.
  */
 
-const BASE = 'https://nominatim.openstreetmap.org';
 const MIN_INTERVAL_MS = 1100;
 
 let lastCall = 0;
@@ -171,7 +171,7 @@ export async function nominatimFetch(
 ): Promise<Response> {
   await throttle(opts.lane ?? 'interactive');
   const signal = opts.signal ?? (opts.timeoutMs ? AbortSignal.timeout(opts.timeoutMs) : undefined);
-  return fetch(`${BASE}/${path}?${params.toString()}`, {
+  return fetch(`${readEnv().integrations.nominatimUrl}/${path}?${params.toString()}`, {
     headers: { 'User-Agent': UA },
     ...(signal ? { signal } : {}),
   });