feat(case-ui): banner-A status rail + V2 segmented tabs (X17 #2)

Implements the approved X17 case-detail redesign foundation (mockups 18c "A" +
18e "V2"):

- New StatusRail component — the integrated status strip (current-phase chip,
  expected-outcome semantic tag, hearing/updated/sync meta inline, agents
  Popover, manual-changer Popover) over the 5-phase pipeline stepper. Lives
  INSIDE the parchment band (CaseHeader), so status is now visible on EVERY tab
  (supersedes the overview-only StatusHero / reverses the prior INV-IA1
  overview-only decision, deliberately).
- CaseHeader absorbs the rail and drops its separate hearing/updated/sync dl
  (those moved into the rail — no duplication).
- Tabs restyled to the V2 "segmented" look (each tab a pill, active = raised
  white card) with per-tab icons.
- Overview tab body is now just documents + agent-activity preview (status left
  the body).
- StatusHero deleted — its content moved wholesale into StatusRail, so no
  parallel status surface remains (G2).

Reuses the shared StatusChanger / StatusGuide / AgentStatusWidget verbatim
(G2). Design-gate: mockups 18c + 18e approved in Claude Design X17.
tsc --noEmit + eslint clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

web-ui/src/app/cases/[caseNumber]/page.tsx

@@ -9,7 +9,6 @@ import { Button } from "@/components/ui/button";
 import { Skeleton } from "@/components/ui/skeleton";
 import { CaseHeader } from "@/components/cases/case-header";
 import { CaseEditDialog } from "@/components/cases/case-edit-dialog";
-import { StatusHero } from "@/components/cases/status-hero";
 import { DocumentsPanel } from "@/components/cases/documents-panel";
 import { DraftsPanel } from "@/components/cases/drafts-panel";
 import { DecisionBlocksPanel } from "@/components/cases/decision-blocks-panel";
@@ -19,7 +18,10 @@ import { AgentActivityPreview } from "@/components/cases/agent-activity-preview"
 import { UploadSheet } from "@/components/documents/upload-sheet";
 import { useCase, useStartWorkflow } from "@/lib/api/cases";
 import { toast } from "sonner";
-import { Play, Loader2 } from "lucide-react";
+import {
+  Play, Loader2, LayoutGrid, Scale, FileText, MessageSquare, Users,
+  type LucideIcon,
+} from "lucide-react";
 
 /*
  * Next 16 breaking change: route params are now a Promise.
@@ -60,23 +62,27 @@ export default function CaseDetailPage({
     );
   }
 
+  const tabDefs: [string, string, LucideIcon][] = [
+    ["overview", "סקירה", LayoutGrid],
+    ["arguments", "טיעונים", Scale],
+    ["decision", "ההחלטה", FileText],
+    ["drafts", "טיוטות והערות", MessageSquare],
+    ["agents", "סוכנים", Users],
+  ];
+
+  // V2 "segmented" tab strip (X17): each tab a pill, active = raised white card.
   const tabsList = (
     <TabsList
       variant="line"
-      className="gap-6 h-auto p-0 rounded-none -mb-px"
+      className="!h-auto gap-1.5 p-0 flex-wrap justify-start"
     >
-      {[
-        ["overview", "סקירה"],
-        ["arguments", "טיעונים"],
-        ["decision", "ההחלטה"],
-        ["drafts", "טיוטות והערות"],
-        ["agents", "סוכנים"],
-      ].map(([value, label]) => (
+      {tabDefs.map(([value, label, Icon]) => (
         <TabsTrigger
           key={value}
           value={value}
-          className="flex-none rounded-none px-0 pb-3.5 pt-0 text-[0.92rem] font-medium text-ink-muted data-active:text-navy data-active:font-semibold data-active:after:bg-gold data-active:after:bottom-0"
+          className="flex-none gap-1.5 rounded-lg border border-transparent px-3.5 py-1.5 text-[0.9rem] font-medium text-ink-soft after:hidden hover:bg-parchment/60 data-active:bg-surface data-active:text-navy data-active:font-semibold data-active:border-rule data-active:shadow-sm [&_svg]:text-ink-light data-active:[&_svg]:text-gold-deep"
         >
+          <Icon className="w-4 h-4" />
           {label}
         </TabsTrigger>
       ))}
@@ -124,22 +130,18 @@ export default function CaseDetailPage({
             <Skeleton className="h-6 w-96" />
           </div>
         ) : (
-          <CaseHeader data={data} actions={bandActions} tabs={tabsList} />
+          <CaseHeader caseNumber={caseNumber} data={data} actions={bandActions} tabs={tabsList} />
         )}
 
-        {/* full-width tab content — status lives ONLY in the overview hero
-            (mockup 18b); the other tabs lose the status rail entirely (INV-IA1). */}
+        {/* full-width tab content — status now lives in the always-visible band
+            StatusRail (banner A, X17), so every tab keeps the status context. */}
         <div className="min-w-0 mt-6">
-          <TabsContent value="overview" className="mt-0 space-y-6">
-            {/* ★ STATUS HERO — the single home for case status (INV-IA1/INV-UI7) */}
-            <StatusHero caseNumber={caseNumber} data={data} />
-
-            {/* documents + agents two-column below the hero (mockup 18b) */}
+          <TabsContent value="overview" className="mt-0">
+            {/* documents + agents two-column (mockup 18j) */}
             <div className="grid gap-6 lg:grid-cols-2 items-start">
               <DocumentsPanel data={data} />
               <AgentActivityPreview caseNumber={caseNumber} />
             </div>
-            {/* decision-editor CTA moved to the band actions (visible on all tabs) */}
           </TabsContent>
 
           <TabsContent value="arguments" className="mt-0">