feat: add localHost option to allow changing of federation host

[kenshineto]

What

Add a userHost option in config that allows instances to use a seperate host for their user ids instead of using the host from the instance url.

For #17212

Why

This mirrors a feature that mastodon has with its LOCAL_URL and WEB_URL options. It allows instances to host their instances on any url without having to compromise their user ids. For example I am running this change on my instance social.freya.cat with all user ids @freya.cat.

Additional info (optional)

Checklist

• Read the contribution guide
• Test working in a local environment
• (If needed) Add story of storybook
• (If needed) Update CHANGELOG.md
• (If possible) Add tests

[github-actions]

このPRによるapi.jsonの差分
差分はありません。
Get diff files from Workflow Page

[github-actions]

Backend memory usage comparison

Before GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	329.23 MB	310.55 MB	-18.67 MB	-5.67%
VmHWM	329.23 MB	311.15 MB	-18.07 MB	-5.49%
VmSize	23123.45 MB	23104.70 MB	-18.75 MB	-0.08%
VmData	1392.72 MB	1375.50 MB	-17.22 MB	-1.23%

After GC

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	329.24 MB	310.56 MB	-18.68 MB	-5.67%
VmHWM	329.24 MB	311.16 MB	-18.08 MB	-5.49%
VmSize	23123.45 MB	23104.70 MB	-18.75 MB	-0.08%
VmData	1392.72 MB	1375.50 MB	-17.22 MB	-1.23%

After Request

Metric	base (MB)	head (MB)	Diff (MB)	Diff (%)
VmRSS	329.69 MB	310.99 MB	-18.69 MB	-5.67%
VmHWM	329.69 MB	311.37 MB	-18.31 MB	-5.55%
VmSize	23123.53 MB	23104.86 MB	-18.66 MB	-0.08%
VmData	1392.81 MB	1375.59 MB	-17.21 MB	-1.23%

See workflow logs for details

[codecov]

Codecov Report

❌ Patch coverage is 32.60870% with 31 lines in your changes missing coverage. Please review.
✅ Project coverage is 63.56%. Comparing base (78435dc) to head (e0f6535).
⚠️ Report is 222 commits behind head on develop.

Files with missing lines	Patch %	Lines
packages/frontend/src/accounts.ts	0.00%	9 Missing ⚠️
packages/frontend/src/preferences/manager.ts	0.00%	0 Missing and 6 partials ⚠️
packages/frontend/src/components/MkPostForm.vue	0.00%	1 Missing and 2 partials ⚠️
...kages/backend/src/server/WellKnownServerService.ts	0.00%	2 Missing ⚠️
packages/frontend/src/utility/get-note-menu.ts	0.00%	2 Missing ⚠️
packages/frontend/src/utility/get-user-menu.ts	0.00%	0 Missing and 2 partials ⚠️
...kages/backend/src/core/RemoteUserResolveService.ts	0.00%	1 Missing ⚠️
packages/backend/src/core/UtilityService.ts	66.66%	1 Missing ⚠️
packages/backend/src/server/ServerService.ts	0.00%	1 Missing ⚠️
packages/backend/src/server/web/FeedService.ts	0.00%	1 Missing ⚠️
... and 3 more

Additional details and impacted files

@@             Coverage Diff              @@
##           develop   #17222       +/-   ##
============================================
+ Coverage    13.97%   63.56%   +49.59%     
============================================
  Files          237     1161      +924     
  Lines        11273   116254   +104981     
  Branches      3728     8365     +4637     
============================================
+ Hits          1575    73902    +72327     
- Misses        7578    40148    +32570     
- Partials      2120     2204       +84     

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[kenshineto]

I use to have this setup where config.url was changed to webUrl, and localUrl was the option added. This ended up changing most of the files within the project, which was honestly too many. So this PR as its written now only modifies the places where userHost should be used instead.

I manually went though every use of url, host, and hostname and figured out (to by best judgement) which one should be used (url or userHost). Hopefully I got them all :)

[kenshineto]

Renamed option form userHost to localHost since userHost is already used in misskey.