feat: 拦截规则 allow/deny 命中也进审批记录(三种 action 全可观测)

此前只有 ask 命中会写 intercept_pending(审批记录);deny 直接拦下、allow 直接放行,
历史里查不到。现让三种 action 命中都留痕,便于观测:

- db: CreateDecidedIntercept —— 一条 insert 直接以最终状态(allowed/denied)落库并盖
  decided_at(复用 intercept_pending 现有合法状态,无需 schema 迁移)。
- intercept: Interceptor.Log —— 非阻塞、best-effort 记录一次规则命中(DB 出错不影响
  工具调用结果)。
- guard: deny 分支记 denied、显式 allow 规则命中记 allowed；无规则命中的放行不记,
  避免全量刷屏。

前端零改动:审批记录/历史页(interceptHistory=全状态、interceptTask=全状态)本就渲染
allowed/denied/pending;pending 过滤仅用于审批按钮区。

intercept/intercept.go

@@ -329,6 +329,17 @@ func defaultMessage(action, name string) string {
 	}
 }
 
+// Log records an allow/deny rule match into intercept_pending as an ALREADY-decided
+// row (status = "allowed" | "denied"), for observability. Unlike HandleAsk it does NOT
+// block and needs no user action — it just makes every rule hit visible on the history
+// page (GET /api/intercept/history) and the task's intercept list. Best-effort: a DB
+// error is swallowed so logging never changes the tool call's outcome. The pending list
+// (status='pending') is unaffected, so it still shows only asks awaiting a decision.
+func (i *Interceptor) Log(ctx context.Context, convID int64, dec Decision, toolName string, input []byte, status string) {
+	taskID, agentName := taskInfoFromCtx(ctx)
+	_, _ = i.db.CreateDecidedIntercept(dec.RuleID, convID, taskID, agentName, toolName, input, status)
+}
+
 // HandleAsk creates a pending approval record and blocks until the user decides
 // (via /api/intercept/pending/{id}/decide) or the per-rule timeout elapses.
 // Returns true if the user approved.