[feature] Configurable max profile fields (#4175)

# Description

> If this is a code change, please include a summary of what you've coded, and link to the issue(s) it closes/implements.
>
> If this is a documentation change, please briefly describe what you've changed and why.

Profile fields, right? So I made them a configurable amount and show them on the instance features. Closes #1876

All changes I did are described in the commits. I tried to cover as much as possible, but I don't know this codebase to know what I've missed. I have tested it manually and it works (settings page, `/api/v1/instances`, server-side validation).

Not done:
- An "Add profile fields" button, so that instances with a high profile fields count (e.g. 100) aren't an issue when trying to skip the profile fields (in some form, accessibility)
- Updating the swagger docs that specify a specific amount of profile fields for the updating endpoint (not sure how to proceed with that)
- Unchecked checklist items

## Checklist

Please put an x inside each checkbox to indicate that you've read and followed it: `[ ]` -> `[x]`

If this is a documentation change, only the first checkbox must be filled (you can delete the others if you want).

- [X] I/we have read the [GoToSocial contribution guidelines](https://codeberg.org/superseriousbusiness/gotosocial/src/branch/main/CONTRIBUTING.md).
- [x] I/we have discussed the proposed changes already, either in an issue on the repository, or in the Matrix chat.
- [X] I/we have not leveraged AI to create the proposed changes.
- [x] I/we have performed a self-review of added code.
- [X] I/we have written code that is legible and maintainable by others.
- [ ] I/we have commented the added code, particularly in hard-to-understand areas.
- [X] I/we have made any necessary changes to documentation.
- [ ] I/we have added tests that cover new code.
- [X] I/we have run tests and they pass locally with the changes.
- [x] I/we have run `go fmt ./...` and `golangci-lint run`.

Notes about checklist:
- ["Approval" to work on this reference](https://matrix.to/#/!mlPctfMHjyopbOnliM:superseriousbusiness.org/$P0Z1Qmny6GNIgxhre69gll8KSD690HC8nVvNpXmu3nU?via=superseriousbusiness.org&via=matrix.org&via=tchncs.de)
- `golangci-lint run` output ignored due to complaining about ffmpeg and some other code I didn't touch

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4175
Reviewed-by: kim <gruf@noreply.codeberg.org>
Co-authored-by: Jackson <jackson@jacksonchen666.com>
Co-committed-by: Jackson <jackson@jacksonchen666.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/web/template/about.tmpl b/web/template/about.tmpl
index 37d115256..c263d73a7 100644
--- a/web/template/about.tmpl
+++ b/web/template/about.tmpl
@@ -81,6 +81,11 @@ Polls can have up to
 <b>{{- .instance.Configuration.Polls.MaxCharactersPerOption }} characters per option</b>.
 {{- end -}}
 
+{{- define "profileLimits" -}}
+Profiles can have up to
+<b>{{- .instance.Configuration.Accounts.MaxProfileFields }} profile fields</b>.
+{{- end -}}
+
 {{- with . }}
 <main class="about">
     <nav class="about-section" aria-labelledby="toc">
@@ -137,6 +142,7 @@ Polls can have up to
             <ul>
                 <li>{{- template "statusLimits" . -}}</li>
                 <li>{{- template "pollLimits" . -}}</li>
+                <li>{{- template "profileLimits" . -}}</li>
                 <li>{{- template "customCSSLimits" . -}}</li>
             </ul>
         </div>