Add benchmark results for fast3 and fast4, implement KeepAliveLspBridge, and add tests for staged strategies

- Added new benchmark result files: compare_2026-02-09_score_fast3.json and compare_2026-02-09_score_fast4.json.
- Implemented KeepAliveLspBridge to maintain a persistent LSP connection across multiple queries, improving performance.
- Created unit tests for staged clustering strategies in test_staged_stage3_fast_strategies.py, ensuring correct behavior of score and dir_rr strategies.

ccw/frontend/src/pages/IssueHubPage.tsx

@@ -15,6 +15,7 @@ import {
 import { IssueHubHeader } from '@/components/issue/hub/IssueHubHeader';
 import { IssueHubTabs, type IssueTab } from '@/components/issue/hub/IssueHubTabs';
 import { IssuesPanel } from '@/components/issue/hub/IssuesPanel';
+import { IssueBoardPanel } from '@/components/issue/hub/IssueBoardPanel';
 import { QueuePanel } from '@/components/issue/hub/QueuePanel';
 import { DiscoveryPanel } from '@/components/issue/hub/DiscoveryPanel';
 import { Button } from '@/components/ui/Button';
@@ -161,6 +162,7 @@ export function IssueHubPage() {
   const renderActionButtons = () => {
     switch (currentTab) {
       case 'issues':
+      case 'board':
         return (
           <>
             <Button variant="outline" onClick={handleIssuesRefresh} disabled={isFetchingIssues}>
@@ -212,6 +214,7 @@ export function IssueHubPage() {
 
       <IssueHubTabs currentTab={currentTab} onTabChange={setCurrentTab} />
       {currentTab === 'issues' && <IssuesPanel onCreateIssue={() => setIsNewIssueOpen(true)} />}
+      {currentTab === 'board' && <IssueBoardPanel />}
       {currentTab === 'queue' && <QueuePanel />}
       {currentTab === 'discovery' && <DiscoveryPanel />}