Navigation: Fix Home logo always going to /login (#62658)

* only redirect to /login when anonymous access is disabled

* only search for dashboards when not logged in if anon access is enabled

* fix go logic

* add unit tests

pkg/api/dtos/frontend_settings.go

@@ -181,6 +181,7 @@ type FrontendSettingsDTO struct {
 	LicenseInfo FrontendSettingsLicenseInfoDTO `json:"licenseInfo"`
 
 	FeatureToggles                   map[string]bool                `json:"featureToggles"`
+	AnonymousEnabled                 bool                           `json:"anonymousEnabled"`
 	RendererAvailable                bool                           `json:"rendererAvailable"`
 	RendererVersion                  string                         `json:"rendererVersion"`
 	SecretsManagerPluginEnabled      bool                           `json:"secretsManagerPluginEnabled"`

pkg/api/frontendsettings.go

@@ -174,6 +174,7 @@ func (hs *HTTPServer) getFrontendSettings(c *contextmodel.ReqContext) (*dtos.Fro
 		},
 
 		FeatureToggles:                   hs.Features.GetEnabled(c.Req.Context()),
+		AnonymousEnabled:                 hs.Cfg.AnonymousEnabled,
 		RendererAvailable:                hs.RenderService.IsAvailable(c.Req.Context()),
 		RendererVersion:                  hs.RenderService.Version(),
 		SecretsManagerPluginEnabled:      secretsManagerPluginEnabled,