Fix validation of empty url in asset profile dialog

The url attribute in the asset profile dialog of the admin control
panel is optional, but leaving it empty made the form fail with "url
must be a URL address". The form initializes the control with an empty
string, which is not skipped by IsOptional, since it only applies to
null and undefined. Transform empty strings to undefined in the DTO so
the validation treats the attribute as absent.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## Unreleased
+
+### Fixed
+
+- Fixed the validation of an empty url in the asset profile dialog of the admin control panel
+
 ## 3.39.0 - 2026-08-01
 
 ### Changed

libs/common/src/lib/dtos/update-asset-profile.dto.ts

@@ -7,7 +7,7 @@ import {
   DataSource,
   Prisma
 } from '@prisma/client';
-import { Type } from 'class-transformer';
+import { Transform, TransformFnParams, Type } from 'class-transformer';
 import {
   IsArray,
   IsBoolean,
@@ -18,6 +18,7 @@ import {
   IsUrl,
   ValidateNested
 } from 'class-validator';
+import { isString } from 'lodash';
 
 import { CountryDto } from './country.dto';
 import { HoldingDto } from './holding.dto';
@@ -96,5 +97,8 @@ export class UpdateAssetProfileDto {
     protocols: ['http', 'https'],
     require_protocol: true
   })
+  @Transform(({ value }: TransformFnParams) =>
+    isString(value) && value.trim() === '' ? undefined : value
+  )
   url?: string;
 }