Implemented admin pane + user permission

internal/api/confmgr.go

@@ -765,3 +765,37 @@ func (h *Handler) checkConfigRule(w http.ResponseWriter, r *http.Request) {
 	}
 	jsonOK(w, confmgr.EvaluateRule(body.Source, body.Values))
 }
+
+// previewConfigRule evaluates a (possibly unsaved) CUE source against a live
+// snapshot of the bound set's target signals, without storing anything. Unlike
+// check (which uses sample/default values), preview reads the current hardware
+// values so the operator sees exactly what the rule would derive from the real
+// configuration. Body: {setId, source}. Returns the captured snapshot plus the
+// rule result (violations + transformed values).
+func (h *Handler) previewConfigRule(w http.ResponseWriter, r *http.Request) {
+	if !h.configEnabled(w) {
+		return
+	}
+	var body struct {
+		SetID  string `json:"setId"`
+		Source string `json:"source"`
+	}
+	if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
+		jsonError(w, http.StatusBadRequest, "invalid JSON: "+err.Error())
+		return
+	}
+	set, err := h.cfg.GetSet(body.SetID)
+	if err != nil {
+		jsonError(w, configStatus(err), err.Error())
+		return
+	}
+	ctx, cancel := context.WithTimeout(r.Context(), 5*time.Second)
+	defer cancel()
+	results := h.readSetSignals(ctx, set)
+	snap := confmgr.Snapshot(set, snapshotReader(results))
+	res := confmgr.EvaluateRule(body.Source, snap.Values)
+	jsonOK(w, struct {
+		Snapshot confmgr.SnapshotResult `json:"snapshot"`
+		Result   confmgr.RuleResult     `json:"result"`
+	}{snap, res})
+}