[chore] Rationalize HTTP return codes for fedi endpoints, other tidying up (#4503)

# 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.

This pull request does some refactoring of the fedi API endpoints and processing functions, and the authenticate + pub key deref functions, to try to return fewer silly HTTP codes like 410 Gone (when a *remote* account is gone, not a local one), and 500 errors where something isn't really an error.

Also does some general tidying up and renaming for consistency.

## 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.
- [x] I/we have commented the added code, particularly in hard-to-understand areas.
- [ ] 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`.

Reviewed-on: https://codeberg.org/superseriousbusiness/gotosocial/pulls/4503
Co-authored-by: tobi <tobi.smethurst@protonmail.com>
Co-committed-by: tobi <tobi.smethurst@protonmail.com>

1 files changed, 5 insertions, 4 deletions

diff --git a/internal/processing/fedi/wellknown.go b/internal/processing/fedi/wellknown.go
index 0e6989803..236f09257 100644
--- a/internal/processing/fedi/wellknown.go
+++ b/internal/processing/fedi/wellknown.go
@@ -47,7 +47,7 @@ var (
 	nodeInfoProtocols = []string{"activitypub"}
 	nodeInfoInbound   = []string{}
 	nodeInfoOutbound  = []string{}
-	nodeInfoMetadata  = make(map[string]interface{})
+	nodeInfoMetadata  = make(map[string]any)
 )
 
 // NodeInfoRelGet returns a well known response giving the path to node info.
@@ -156,11 +156,12 @@ func (p *Processor) HostMetaGet() *apimodel.HostMeta {
 }
 
 // WebfingerGet handles the GET for a webfinger resource. Most commonly, it will be used for returning account lookups.
-func (p *Processor) WebfingerGet(ctx context.Context, requestedUsername string) (*apimodel.WellKnownResponse, gtserror.WithCode) {
+func (p *Processor) WebfingerGet(ctx context.Context, requestedUser string) (*apimodel.WellKnownResponse, gtserror.WithCode) {
 	// Get the local account the request is referring to.
-	requestedAccount, err := p.state.DB.GetAccountByUsernameDomain(ctx, requestedUsername, "")
+	requestedAccount, err := p.state.DB.GetAccountByUsernameDomain(ctx, requestedUser, "")
 	if err != nil {
-		return nil, gtserror.NewErrorNotFound(fmt.Errorf("database error getting account with username %s: %s", requestedUsername, err))
+		err := gtserror.Newf("db error getting account %s: %s", requestedUser, err)
+		return nil, gtserror.NewErrorNotFound(err)
 	}
 
 	return &apimodel.WellKnownResponse{