refactor: modularize audit and harden build validation

audit/internal/webui/task_page.go

@@ -2,7 +2,6 @@ package webui
 
 import (
 	"encoding/json"
-	"fmt"
 	"html"
 	"net/http"
 	"os"
@@ -225,13 +224,6 @@ func loadTaskReportFragment(task Task) string {
 	return string(data)
 }
 
-func taskArtifactDownloadLink(task Task, absPath string) string {
-	if strings.TrimSpace(absPath) == "" {
-		return ""
-	}
-	return fmt.Sprintf(`/export/file?path=%s`, absPath)
-}
-
 func (h *handler) taskSamplesForRequest(r *http.Request) (Task, []platform.LiveMetricSample, time.Time, time.Time, bool) {
 	id := r.PathValue("id")
 	taskPtr, ok := globalQueue.findByID(id)