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

rust/crates/mnote-web/src/routes/knowledge_rag.rs

@@ -369,7 +369,27 @@ pub async fn ingest(
     let mut expanded_count = 0usize;
     let mut seen_sources = BTreeSet::<String>::new();
     let force = body.force.unwrap_or(false);
-    for source in body.sources {
+    let mut requested_sources = body.sources;
+    if requested_sources.is_empty() {
+        requested_sources = registry
+            .indexed_roots
+            .iter()
+            .map(|root| KnowledgeRagSourceInput {
+                source_path: Some(root.root_relative_path.clone()),
+                path: None,
+                parser_hint: None,
+            })
+            .collect();
+    }
+    if requested_sources.is_empty() {
+        return Err(WebError::bad_request_code(
+            "knowledge_rag_source_required",
+            "资料库索引缺少 sourcePath，且没有可重建的已保存索引范围",
+        )
+        .with_context(&context));
+    }
+
+    for source in requested_sources {
         let source_path = source.source_path.or(source.path).ok_or_else(|| {
             WebError::bad_request_code("knowledge_rag_source_required", "资料库索引缺少 sourcePath")
                 .with_context(&context)
@@ -1087,7 +1107,8 @@ fn normalize_knowledge_rag_search_mode(mode: Option<&str>) -> String {
         Some("hybrid") => "hybrid".into(),
         Some("naive" | "vector") => "naive".into(),
         Some("mix" | "mixed") => "mix".into(),
-        _ => "mix".into(),
+        Some(_) => "mix".into(),
+        None => "exact".into(),
     }
 }
 
@@ -4718,7 +4739,7 @@ mod tests {
             normalize_knowledge_rag_search_mode(Some("hybrid")),
             "hybrid"
         );
-        assert_eq!(normalize_knowledge_rag_search_mode(None), "mix");
+        assert_eq!(normalize_knowledge_rag_search_mode(None), "exact");
     }
 
     #[test]

rust/crates/mnote-web/src/ssr/pages/layout.rs

@@ -568,6 +568,11 @@ mod tests {
         assert!(SIDEBAR_TREE_RUNTIME_JS.contains("pruneKnowledgeRagRegistry"));
         assert!(SIDEBAR_TREE_RUNTIME_JS.contains("setKnowledgeRagSourceFilter"));
         assert!(SIDEBAR_TREE_RUNTIME_JS.contains("mnote:knowledge-rag-source-updated"));
+        assert!(
+            SIDEBAR_TREE_RUNTIME_JS.contains(r#"<option value="exact" selected>关键词</option>"#)
+        );
+        assert!(SIDEBAR_TREE_RUNTIME_JS
+            .contains(r#"data-search-switch="knowledge" role="switch" aria-checked="true""#));
         assert!(SIDEBAR_FILETREE_COMMAND_RUNTIME_JS.contains("knowledgeRagSourceRelativePath"));
         assert!(SIDEBAR_FILETREE_COMMAND_RUNTIME_JS.contains("supportsKnowledgeRagSource"));
         assert!(!SIDEBAR_FILETREE_COMMAND_RUNTIME_JS.contains("runLocalOcr"));