feat(triage): Ivanti findings trend chart + rename Reporting to Vulnerability Triage

Add time-based open/closed tracking for Ivanti findings (Tier 2 from
the reporting recommendations doc) and rename the Reporting page to
Vulnerability Triage to better reflect its purpose.

Backend — ivantiFindings.js:
  - Create ivanti_counts_history table (appended on every sync, never
    overwritten — Option B from design discussion)
  - INSERT snapshot after each successful syncClosedCount() call
  - GET /api/ivanti/findings/counts/history endpoint — returns last
    snapshot per calendar day using ROW_NUMBER window function, so
    multiple daily syncs collapse to the end-of-day value

Frontend:
  - New IvantiCountsChart component: collapsible dual-line chart
    (open vs closed) with dark tooltip, delta label showing change
    since previous day, and graceful no-data states
  - Chart placed between the donut metrics panel and the findings table
    on the Vulnerability Triage page
  - Renamed page: 'reporting' → 'triage' (page ID, nav label, component
    export, all cross-file references)
  - ComplianceDetailPanel "View in Reporting" link updated to "View in
    Triage" and navigates to the correct page ID

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/App.js

@@ -10,7 +10,7 @@ import KnowledgeBaseModal from './components/KnowledgeBaseModal';
 import KnowledgeBaseViewer from './components/KnowledgeBaseViewer';
 import NavDrawer from './components/NavDrawer';
 import CalendarWidget from './components/CalendarWidget';
-import ReportingPage from './components/pages/ReportingPage';
+import VulnerabilityTriagePage from './components/pages/ReportingPage';
 import KnowledgeBasePage from './components/pages/KnowledgeBasePage';
 import ExportsPage from './components/pages/ExportsPage';
 import CompliancePage from './components/pages/CompliancePage';
@@ -966,14 +966,14 @@ export default function App() {
         currentPage={currentPage}
         onNavigate={(page) => {
           // Clear contextual filters when navigating directly via the nav drawer
-          if (page === 'reporting') { setCalendarFilter(null); setReportingExcFilter(null); }
+          if (page === 'triage') { setCalendarFilter(null); setReportingExcFilter(null); }
           setCurrentPage(page);
         }}
       />
       {/* Scanning line effect */}
       <div className="scan-line"></div>
 
-      <div className={`${currentPage === 'reporting' ? 'w-full' : 'max-w-7xl mx-auto'} relative z-10`}>
+      <div className={`${currentPage === 'triage' ? 'w-full' : 'max-w-7xl mx-auto'} relative z-10`}>
         {/* Header */}
         <div className="mb-8">
           <div className="flex justify-between items-start mb-6">
@@ -1043,7 +1043,7 @@ export default function App() {
         </div>
 
         {/* Page content */}
-        {currentPage === 'reporting'      && <ReportingPage filterDate={calendarFilter} filterEXC={reportingExcFilter} />}
+        {currentPage === 'triage'         && <VulnerabilityTriagePage filterDate={calendarFilter} filterEXC={reportingExcFilter} />}
         {currentPage === 'compliance'     && <CompliancePage onNavigate={setCurrentPage} />}
         {currentPage === 'knowledge-base' && <KnowledgeBasePage />}
         {currentPage === 'exports'        && <ExportsPage />}
@@ -2231,7 +2231,7 @@ export default function App() {
               <CalendarWidget
                 onDateClick={(dateStr) => {
                   setCalendarFilter(dateStr);
-                  setCurrentPage('reporting');
+                  setCurrentPage('triage');
                 }}
               />
             </div>