Cleanup: Finalize template context integration and remove legacy code

- Replaced legacy TemplateContext calls with structured TemplateData usage
- Removed unused variables and redundant storage calls in notifications handler
- Ensured consistent use of BuildTemplateData across user-facing handlers
- Resolved all compile-time errors from refactor
- Ready for runtime testing and further layout integration

helpers/pages.go

@@ -4,10 +4,12 @@ package helpers
 import (
 	"html/template"
 	"net/http"
+
+	"synlotto-website/models"
 )
 
 func Render403(w http.ResponseWriter, r *http.Request) {
-	context := TemplateContext(w, r)
+	context := TemplateContext(w, r, models.TemplateData{})
 	tmpl := template.Must(template.New("").Funcs(TemplateFuncs()).ParseFiles(
 		"templates/layout.html",
 		"templates/error/403.html",