Unlock Name Service (and maybe other services with Character selector) will skip validation if no characters exist in the account

Ported from: https://github.com/chromiecraft/chromiecraft/issues/9269

### Bug Title

Unlock Name Service (and maybe other services with Character selector) will skip validation if no characters exist in the account

### Current Behaviour

Currently for `Unlock Name` if your account does not have any character it will entirely skip validation (doesn't show the selector either) and allow you to spend/buy the service without actually getting it or being valid.

This may apply to other services that use the characte rselector

### Expected Behaviour

If you don't have any character should tell you that you can't use this service, it requires at least 1 character to it renamed to the name being unlocked

### Steps to Reproduce

https://www.chromiecraft.com/en/rewards-catalogue/

### Browser

Chrome

### Device

Desktop

### Operating System

W11

### Extra Information

_No response_

### URL

_No response_
### Operating system

Ubuntu 22.04

### Modules

- [mod-1v1-arena](https://github.com/azerothcore/mod-1v1-arena)
- [mod-ah-bot](https://github.com/azerothcore/mod-ah-bot)
- [mod-anticheat](https://github.com/azerothcore/mod-anticheat)
- [mod-arena-3v3-solo-queue](https://github.com/azerothcore/mod-arena-3v3-solo-queue)
- [mod-arena-replay](https://github.com/azerothcore/mod-arena-replay)
- [mod-bg-item-reward](https://github.com/azerothcore/mod-bg-item-reward)
- [mod-breaking-news-override](https://github.com/azerothcore/mod-breaking-news-override)
- [mod-cfbg](https://github.com/azerothcore/mod-cfbg)
- [mod-chat-transmitter](https://github.com/azerothcore/mod-chat-transmitter)
- [mod-chromie-xp](https://github.com/azerothcore/mod-chromie-xp)
- [mod-chromiecraft-smartstone](https://github.com/chromiecraft/mod-chromiecraft-smartstone)
- [mod-costumes](https://github.com/azerothcore/mod-costumes)
- [mod-cta-switch](https://github.com/azerothcore/mod-cta-switch)
- [mod-desertion-warnings](https://github.com/azerothcore/mod-desertion-warnings)
- [mod-dmf-switch](https://github.com/azerothcore/mod-dmf-switch)
- [mod-duel-reset](https://github.com/azerothcore/mod-duel-reset)
- [mod-eluna](https://github.com/azerothcore/mod-eluna)
- [mod-evade-logging](https://github.com/heyitsbench/mod-evade-logging)
- [mod-instanced-worldbosses](https://github.com/nyeriah/mod-instanced-worldbosses)
- [mod-ip-tracker](https://github.com/azerothcore/mod-ip-tracker)
- [mod-low-level-arena](https://github.com/azerothcore/mod-low-level-arena)
- [mod-low-level-rbg](https://github.com/azerothcore/mod-low-level-rbg)
- [mod-multi-client-check](https://github.com/azerothcore/mod-multi-client-check)
- [mod-npc-spectator](https://github.com/gozzim/mod-npc-spectator)
- [mod-progression-system](https://github.com/azerothcore/mod-progression-system)
- [mod-pvp-quests](https://github.com/azerothcore/mod-pvp-quests)
- [mod-pvp-titles](https://github.com/azerothcore/mod-pvp-titles)
- [mod-pvpstats-announcer](https://github.com/azerothcore/mod-pvpstats-announcer)
- [mod-queue-list-cache](https://github.com/azerothcore/mod-queue-list-cache)
- [mod-rdf-expansion](https://github.com/azerothcore/mod-rdf-expansion)
- [mod-resurrection-scroll](https://github.com/azerothcore/mod-resurrection-scroll)
- [mod-transmog](https://github.com/azerothcore/mod-transmog)
- [mod-weekend-xp](https://github.com/azerothcore/mod-weekend-xp)
- [mod-zone-difficulty](https://github.com/azerothcore/mod-zone-difficulty)
- [lua-CarbonCopy](https://github.com/55Honey/Acore_CarbonCopy)
- [lua-eventScripts](https://github.com/55Honey/Acore_eventScripts)
- [lua-ExchangeNpc](https://github.com/55Honey/Acore_ExchangeNpc)
- [lua-LevelUpReward](https://github.com/55Honey/Acore_LevelUpReward)
- [lua-RecruitAFriend](https://github.com/55Honey/Acore_RecruitAFriend)
- [lua-SendAndBind](https://github.com/55Honey/Acore_SendAndBind)
- [lua-TempAnnouncements](https://github.com/55Honey/Acore_TempAnnouncements)
- [lua-Zonecheck](https://github.com/55Honey/acore_Zonecheck)

### Server

ChromieCraft

Start by reproducing the issue at the ChromieCraft rewards catalogue with an account that has no characters, focusing on Unlock Name and other services with a character selector. Trace the validation and purchase flow, then verify that an account without characters is told the service cannot be used and cannot spend or buy it.

Written by the indexing model from the issue text.