feat(frontend): 全局企业筛选同步 — 各页面显示企业名标签

- 新增 useCompanyName hook 和 CompanyNameTag 组件
- 20+ investor 页面添加 CompanyNameTag 显示企业名
- 表格型页面（agents/agreements/board/weak-signals/talents/reports）新增企业列
- 卡片型页面（risks/synergies/sentinels/alpha/exit-signals/okrs/aars/events/tasks/pre-mortems/nudges/product-diagnostics/peer-circles）添加企业名标签
- customer-success 改用 CompanyNameTag 替代手动 company_name 显示
- PlanCard 组件添加企业名标签
- 编译验证通过

frontend/src/app/(investor)/sentinels/page.tsx

@@ -2,6 +2,7 @@
 
 import { useState } from "react";
 import { useScopeEffect } from "@/lib/company-scope";
+import { CompanyNameTag } from "@/components/shared/CompanyNameTag";
 import { listDecisionSentinels } from "@/lib/api-v2";
 import { PageContainer, Badge} from "@/components/shared/PageContainer";
 import { LoadingSpinner } from "@/components/shared/LoadingSpinner";
@@ -9,6 +10,7 @@ import { EmptyState } from "@/components/shared/EmptyState";
 
 /** 决策前哨项。 */
 interface DecisionSentinel {
+  company_id?: string;
   decision_type: string;
   title: string;
   status: string;
@@ -39,6 +41,7 @@ export default function SentinelsPage() {
               <div className="flex items-center justify-between">
                 <div className="flex items-center gap-2">
                   <Badge color="blue">{item.decision_type}</Badge>
+                  <CompanyNameTag companyId={item.company_id} />
                   <h3 className="font-medium text-gray-900">{item.title}</h3>
                 </div>
                 <Badge color={item.status === "acted" ? "green" : item.status === "analyzed" ? "amber" : "gray"}>