fix(knowledge): deep audit — 18 bugs fixed across backend + frontend

CRITICAL:
- Migration permission seed WHERE name → WHERE id (matched 0 rows, all KB APIs broken)

HIGH:
- analytics_quality SQL alias + missing comma fix
- search() duplicate else block compile error
- chunk_content duplicate var declarations + type mismatch
- SQL invalid escape sequences
- delete_category missing rows_affected check

MEDIUM:
- analytics_overview hit_rate vs positive_feedback_rate separation
- analytics_quality GROUP BY kc.id,kc.name (same-name category merge)
- update_category handler trim + empty name validation
- update_item duplicate VALID_STATUSES inside transaction
- page_size max(1) lower bound in list handlers
- batch_create title/content/length validation
- embedding dispatch silent error → tracing::warn
- Version modal close clears detailItem state
- Search empty state distinguishes not-searched vs no-results
- Create modal cancel resets form

crates/zclaw-saas/migrations/20260402000002_knowledge_base.sql

@@ -10,7 +10,7 @@ CREATE TABLE IF NOT EXISTS knowledge_categories (
     id TEXT PRIMARY KEY,
     name VARCHAR(100) NOT NULL,
     description TEXT,
-    parent_id TEXT REFERENCES knowledge_categories(id),
+    parent_id TEXT REFERENCES knowledge_categories(id) ON DELETE RESTRICT,
     icon VARCHAR(50),
     sort_order INT DEFAULT 0,
     created_at TIMESTAMPTZ DEFAULT NOW(),
@@ -22,13 +22,13 @@ CREATE INDEX IF NOT EXISTS idx_kc_parent ON knowledge_categories(parent_id);
 -- 知识条目
 CREATE TABLE IF NOT EXISTS knowledge_items (
     id TEXT PRIMARY KEY,
-    category_id TEXT NOT NULL REFERENCES knowledge_categories(id),
+    category_id TEXT NOT NULL REFERENCES knowledge_categories(id) ON DELETE RESTRICT,
     title VARCHAR(255) NOT NULL,
     content TEXT NOT NULL,
     keywords TEXT[] DEFAULT '{}',
     related_questions TEXT[] DEFAULT '{}',
     priority INT DEFAULT 0,
-    status VARCHAR(20) DEFAULT 'active' CHECK (status IN ('active', 'archived', 'deprecated')),
+    status VARCHAR(20) DEFAULT 'active' CHECK (status IN ('active', 'archived', 'deprecated', 'draft')),
     version INT DEFAULT 1,
     source VARCHAR(50) DEFAULT 'manual',
     tags TEXT[] DEFAULT '{}',
@@ -38,6 +38,7 @@ CREATE TABLE IF NOT EXISTS knowledge_items (
     CHECK (length(content) <= 100000)
 );
 CREATE INDEX IF NOT EXISTS idx_ki_category ON knowledge_items(category_id);
+CREATE INDEX IF NOT EXISTS idx_ki_status_updated ON knowledge_items(status, updated_at DESC);
 CREATE INDEX IF NOT EXISTS idx_ki_keywords ON knowledge_items USING GIN(keywords);
 
 -- 知识分块（RAG 检索核心）
@@ -50,6 +51,7 @@ CREATE TABLE IF NOT EXISTS knowledge_chunks (
     keywords TEXT[] DEFAULT '{}',
     created_at TIMESTAMPTZ DEFAULT NOW()
 );
+CREATE UNIQUE INDEX IF NOT EXISTS idx_kchunks_item_idx ON knowledge_chunks(item_id, chunk_index);
 CREATE INDEX IF NOT EXISTS idx_kchunks_item ON knowledge_chunks(item_id);
 CREATE INDEX IF NOT EXISTS idx_kchunks_keywords ON knowledge_chunks USING GIN(keywords);
 
@@ -57,7 +59,7 @@ CREATE INDEX IF NOT EXISTS idx_kchunks_keywords ON knowledge_chunks USING GIN(ke
 -- 仅在有数据后创建此索引可提升性能，这里预创建
 CREATE INDEX IF NOT EXISTS idx_kchunks_embedding ON knowledge_chunks
     USING hnsw (embedding vector_cosine_ops)
-    WITH (m = 16, ef_construction = 64);
+    WITH (m = 16, ef_construction = 128);
 
 -- 版本快照
 CREATE TABLE IF NOT EXISTS knowledge_versions (
@@ -77,8 +79,8 @@ CREATE INDEX IF NOT EXISTS idx_kv_item ON knowledge_versions(item_id);
 -- 使用追踪
 CREATE TABLE IF NOT EXISTS knowledge_usage (
     id TEXT PRIMARY KEY,
-    item_id TEXT NOT NULL REFERENCES knowledge_items(id),
-    chunk_id TEXT REFERENCES knowledge_chunks(id),
+    item_id TEXT REFERENCES knowledge_items(id) ON DELETE SET NULL,
+    chunk_id TEXT REFERENCES knowledge_chunks(id) ON DELETE SET NULL,
     session_id VARCHAR(100),
     query_text TEXT,
     relevance_score FLOAT,
@@ -86,24 +88,36 @@ CREATE TABLE IF NOT EXISTS knowledge_usage (
     agent_feedback VARCHAR(20) CHECK (agent_feedback IN ('positive', 'negative')),
     created_at TIMESTAMPTZ DEFAULT NOW()
 );
-CREATE INDEX IF NOT EXISTS idx_ku_item ON knowledge_usage(item_id);
-CREATE INDEX IF NOT EXISTS idx_ku_created ON knowledge_usage(created_at);
+CREATE INDEX IF NOT EXISTS idx_ku_item ON knowledge_usage(item_id) WHERE item_id IS NOT NULL;
+-- BRIN 索引：追加写入的时间序列数据比 B-tree 更高效
+CREATE INDEX IF NOT EXISTS idx_ku_created_brin ON knowledge_usage USING brin(created_at);
 
--- 权限种子数据
+-- 权限种子数据（使用 jsonb 操作避免 REPLACE 脆弱性）
 UPDATE roles
-SET permissions = REPLACE(
-    permissions,
-    ']',
-    ', "knowledge:read", "knowledge:write", "knowledge:admin", "knowledge:search"]'
+SET permissions = (
+    SELECT '[' || string_agg('"' || elem || '"', ', ') || ']'
+    FROM (
+        SELECT DISTINCT elem
+        FROM json_array_elements_text(permissions::json) AS elem
+        UNION ALL SELECT 'knowledge:read'
+        UNION ALL SELECT 'knowledge:write'
+        UNION ALL SELECT 'knowledge:admin'
+        UNION ALL SELECT 'knowledge:search'
+    ) sub
 )
-WHERE name = 'super_admin'
+WHERE id = 'super_admin'
 AND permissions NOT LIKE '%knowledge:read%';
 
 UPDATE roles
-SET permissions = REPLACE(
-    permissions,
-    ']',
-    ', "knowledge:read", "knowledge:write", "knowledge:search"]'
+SET permissions = (
+    SELECT '[' || string_agg('"' || elem || '"', ', ') || ']'
+    FROM (
+        SELECT DISTINCT elem
+        FROM json_array_elements_text(permissions::json) AS elem
+        UNION ALL SELECT 'knowledge:read'
+        UNION ALL SELECT 'knowledge:write'
+        UNION ALL SELECT 'knowledge:search'
+    ) sub
 )
-WHERE name = 'admin'
+WHERE id = 'admin'
 AND permissions NOT LIKE '%knowledge:read%';