Adjust story summary recall thresholds

modules/story-summary/vector/text-search.js

@@ -0,0 +1,85 @@
+// ═══════════════════════════════════════════════════════════════════════════
+// Text Search - L2 事件文本检索（MiniSearch）
+// 与向量检索互补，通过 RRF 融合
+// ═══════════════════════════════════════════════════════════════════════════
+
+import MiniSearch from '../../../libs/minisearch.mjs';
+
+let idx = null;
+let lastRevision = null;
+
+/**
+ * 中文逐字 + 英数字串分词
+ */
+function tokenize(text) {
+    return String(text || '').match(/[\u4e00-\u9fff]|[a-zA-Z0-9]+/g) || [];
+}
+
+/**
+ * 去掉 summary 末尾的楼层标记
+ */
+function stripFloorTag(s) {
+    return String(s || '').replace(/\s*\(#\d+(?:-\d+)?\)\s*$/, '').trim();
+}
+
+/**
+ * 构建/更新事件文本索引
+ */
+export function ensureEventTextIndex(events, revision) {
+    if (!events?.length) {
+        idx = null;
+        lastRevision = null;
+        return;
+    }
+
+    if (idx && revision === lastRevision) return;
+
+    try {
+        idx = new MiniSearch({
+            fields: ['title', 'summary', 'participants'],
+            storeFields: ['id'],
+            tokenize,
+        });
+
+        idx.addAll(events.map(e => ({
+            id: e.id,
+            title: e.title || '',
+            summary: stripFloorTag(e.summary),
+            participants: (e.participants || []).join(' '),
+        })));
+
+        lastRevision = revision;
+    } catch (e) {
+        console.error('[text-search] Index build failed:', e);
+        idx = null;
+        lastRevision = null;
+    }
+}
+
+/**
+ * 文本检索事件
+ */
+export function searchEventsByText(queryText, limit = 80) {
+    if (!idx || !queryText?.trim()) return [];
+
+    try {
+        const res = idx.search(queryText, {
+            limit,
+            boost: { title: 2, participants: 1.5, summary: 1 },
+            fuzzy: 0.2,
+            prefix: true,
+        });
+        return res.map((r, i) => ({ id: r.id, textRank: i + 1 }));
+    } catch (e) {
+        console.error('[text-search] Search failed:', e);
+        return [];
+    }
+}
+
+/**
+ * 清理索引
+ */
+export function clearEventTextIndex() {
+    idx = null;
+    lastRevision = null;
+}