PAS-556 | Add support for credential hints to the register flow

[Tyrrrz]

Ticket

• Closes https://bitwarden.atlassian.net/browse/PAS-556

Description

This adds an ability to provide credential hints to the /register endpoint.

Shape

Screenshots

Checklist

I did the following to ensure that my changes were tested thoroughly:

• I used the Playground to verify that setting different hints results in different behavior

I did the following to ensure that my changes do not introduce security vulnerabilities:

• __

[codecov]

Codecov Report

Attention: Patch coverage is 52.38095% with 10 lines in your changes missing coverage. Please review.

Project coverage is 34.84%. Comparing base (4d08754) to head (e64329d).
Report is 3 commits behind head on main.

Files	Patch %	Lines
...nConsole/Pages/App/Playground/NewAccount.cshtml.cs	0.00%	9 Missing ⚠️
src/Service/TokenService.cs	87.50%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #670      +/-   ##
==========================================
- Coverage   34.85%   34.84%   -0.01%     
==========================================
  Files         565      565              
  Lines       30945    30961      +16     
  Branches      923      924       +1     
==========================================
+ Hits        10785    10788       +3     
- Misses      20018    20031      +13     
  Partials      142      142              

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