feat: 漏洞新增 severity=critical(严重) 与 name(漏洞名称)字段

severity 严重级:
- report_finding 工具 severity 说明改为 critical|high|medium|low
- DB 排序 CASE、report 报告 sevRank、FindingStats 增加 critical
- 前端 Severity 类型、status.ts 新增 rose 色调(实心高强调,视觉高于高危)、
  发现页严重度筛选/统计卡、任务发现 Tab 排序、dashboard 汇总均加入严重

name 漏洞名称:
- findings 表加 name 列(schema + ALTER TABLE ADD COLUMN IF NOT EXISTS 补旧库)
- report_finding 工具新增 name 入参(非必填),写入 node payload 与独立 findings 行
- DBFinding/AddFinding/AddStandaloneFinding、FindingDTO、findingPayload、report 全链路透传
- 发现列表页与任务发现 Tab 展示 name,为空时回退 vulnclass;vulnclass 移到展开详情「类型」
- report 报告标题优先 name,回退 vulnclass

无 CHECK 约束,旧库仅需补 name 列;critical/name 均向后兼容。
db 测试补充 critical 排序/统计与 name 往返断言。

db/exploration.go

@@ -632,6 +632,7 @@ FROM activity WHERE exploration_id=$1 AND id>$2 ORDER BY id LIMIT $3`, s.expID,
 //   - Worker != ""  → filter by worker name (Main = "mainagent", Plan = "planner").
 //     Goal Agent 的第 0 轮拆解也以 worker="planner" 落库，故 Plan 会话完整覆盖 Goal+Planner。
 //   - NodeID != nil → a Worker session, filtered by node_id (= intent id).
+//
 // A zero value (both empty) matches the whole task (no session filter).
 type ActivitySessionFilter struct {
 	Worker string
@@ -885,6 +886,6 @@ FROM activity WHERE exploration_id=$1 AND kind<>'thinking' AND id IN (`+strings.
 // AddStandaloneFinding writes a finding to the standalone findings table, which
 // persists across task deletion (task_id / node_id become NULL when the task or
 // exploration node is deleted). taskID and nodeID may be 0 (stored as NULL).
-func (s *ExplorationStore) AddStandaloneFinding(taskID, nodeID int64, vulnclass, severity, summary, evidence, worker string, assetIDs []int64) (int64, error) {
-	return s.db.AddFinding(taskID, nodeID, vulnclass, severity, summary, evidence, worker, assetIDs)
+func (s *ExplorationStore) AddStandaloneFinding(taskID, nodeID int64, vulnclass, name, severity, summary, evidence, worker string, assetIDs []int64) (int64, error) {
+	return s.db.AddFinding(taskID, nodeID, vulnclass, name, severity, summary, evidence, worker, assetIDs)
 }