fix(rag): default search to keyword and rebuild saved roots

rust/crates/mnote-web/browser/sidebar-page-settings-runtime.js

@@ -670,7 +670,7 @@ export function createSidebarPageSettingsRuntime(context) {
             '</div>' +
             '<div class="wolai-page-settings-index-actions">' +
               '<button type="button" data-knowledge-rag-action="refresh">刷新状态</button>' +
-              '<button type="button" data-knowledge-rag-action="ingest">索引来源</button>' +
+              '<button type="button" data-knowledge-rag-action="ingest">索引/重建来源</button>' +
               '<button type="button" data-knowledge-rag-action="prune">清除失效记录</button>' +
               '<button type="button" data-knowledge-rag-action="open-dashboard">打开 LightRAG</button>' +
             '</div>' +
@@ -1058,6 +1058,17 @@ export function createSidebarPageSettingsRuntime(context) {
     });
   }
 
+  function knowledgeRagIndexedRootValues() {
+    var status = currentKnowledgeRagSummary().status || {};
+    var registry = status.registry && typeof status.registry === 'object' ? status.registry : {};
+    var roots = Array.isArray(registry.indexedRoots) ? registry.indexedRoots : [];
+    return roots.map(function(root) {
+      return String(root && (root.rootRelativePath || root.root_relative_path) || '').trim();
+    }).filter(Boolean).filter(function(value, index, list) {
+      return list.indexOf(value) === index;
+    });
+  }
+
   function knowledgeRagCurrentFilter() {
     return pageUiState.knowledgeRagSourceFilter || 'attention';
   }
@@ -1503,11 +1514,12 @@ export function createSidebarPageSettingsRuntime(context) {
   async function ingestKnowledgeRagSources() {
     if (!knowledgeRagIsAvailable()) return;
     var sources = knowledgeRagSourceInputValues();
+    if (!sources.length) sources = knowledgeRagIndexedRootValues();
     if (!sources.length) {
       pageUiState.knowledgeRagSummary = Object.assign({}, currentKnowledgeRagSummary(), {
         scopeKey: knowledgeRagScopeKey(),
         loading: false,
-        error: '请先填写要索引的资料路径'
+        error: '请先填写要索引的资料路径，或保留至少一个已保存的索引范围'
       });
       renderKnowledgeRagSettings();
       return;