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)/weak-signals/page.tsx

@@ -2,6 +2,7 @@
 
 import { useState } from "react";
 import { useScopeEffect } from "@/lib/company-scope";
+import { CompanyNameTag } from "@/components/shared/CompanyNameTag";
 import { listWeakSignals } 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";
 
 /** 弱信号项。 */
 interface WeakSignal {
+  company_id?: string;
   signal_type: string;
   content: string;
   confidence: number;
@@ -45,6 +47,7 @@ export default function WeakSignalsPage() {
           <table className="min-w-full divide-y divide-gray-200 text-sm">
             <thead className="bg-gray-50">
               <tr>
+                <th className="px-4 py-2 text-left font-medium text-gray-500">企业</th>
                 <th className="px-4 py-2 text-left font-medium text-gray-500">类型</th>
                 <th className="px-4 py-2 text-left font-medium text-gray-500">内容</th>
                 <th className="px-4 py-2 text-left font-medium text-gray-500">置信度</th>
@@ -55,6 +58,7 @@ export default function WeakSignalsPage() {
             <tbody className="divide-y divide-gray-100 bg-white">
               {items.map((item, i) => (
                 <tr key={i}>
+                  <td className="px-4 py-2"><CompanyNameTag companyId={item.company_id} /></td>
                   <td className="px-4 py-2">
                     <Badge color="blue">{SIGNAL_TYPE_LABELS[item.signal_type] ?? item.signal_type}</Badge>
                   </td>