feat(home): tram arrival widget for Ул. Антонова-Овсеенко

Adds a live transit widget on the home screen showing upcoming trams
at both directions of the stop: toward Новочеркасская (stopID 16226)
and toward пр. Большевиков (stopID 16354).

- /api/transport proxies the СПб ORGP endpoint /stop/{id}/arriving
  (DataTables POST format, JSON response with route number + minutes).
  No auth required, free.
- TransportWidget renders two glassmorphism cards with route badges,
  minutes-to-arrival, wheelchair indicator; imminent (<=2 min) arrivals
  get a colored highlight. Filters to trams 23/27/39; refreshes every 30s.
- Route colors: 23 blue, 27 amber, 39 purple.

app/api/transport/route.ts

@@ -0,0 +1,67 @@
+export const dynamic = 'force-dynamic'
+import { NextResponse } from 'next/server'
+
+const ORGP_BASE = 'https://transport.orgp.spb.ru'
+
+export async function GET(req: Request) {
+  const { searchParams } = new URL(req.url)
+  const stopId = searchParams.get('stopId')
+  if (!stopId || !/^\d+$/.test(stopId)) {
+    return NextResponse.json({ error: 'stopId required (digits)' }, { status: 400 })
+  }
+
+  const body = new URLSearchParams({
+    sEcho: '1',
+    iColumns: '5',
+    sColumns: 'index,routeNumber,timeToArrive,parkNumber,wheelchair',
+    iDisplayStart: '0',
+    iDisplayLength: '-1',
+    sNames: 'index,routeNumber,timeToArrive,parkNumber,wheelchair',
+  })
+
+  try {
+    const upstream = await fetch(
+      `${ORGP_BASE}/Portal/transport/stop/${encodeURIComponent(stopId)}/arriving`,
+      {
+        method: 'POST',
+        headers: {
+          'X-Requested-With': 'XMLHttpRequest',
+          'Content-Type': 'application/x-www-form-urlencoded; charset=UTF-8',
+          'Accept': 'application/json, text/javascript, */*; q=0.01',
+        },
+        body: body.toString(),
+        cache: 'no-store',
+        // @ts-ignore  next-internal option for timeout
+        next: { revalidate: 0 },
+      }
+    )
+
+    if (!upstream.ok) {
+      return NextResponse.json(
+        { error: `upstream_${upstream.status}`, arrivals: [] },
+        { status: 502 }
+      )
+    }
+
+    const data = await upstream.json()
+    const arrivals = Array.isArray(data?.aaData)
+      ? data.aaData.map((row: any[]) => ({
+          route: String(row[1] ?? ''),
+          minutes: Number(row[2] ?? 0),
+          park: String(row[3] ?? ''),
+          wheelchair: Boolean(row[4]),
+        }))
+      : []
+
+    return NextResponse.json({
+      stopId,
+      arrivals,
+      fetchedAt: new Date().toISOString(),
+    })
+  } catch (e: any) {
+    return NextResponse.json(
+      { error: e?.message || 'fetch_failed', arrivals: [] },
+      { status: 502 }
+    )
+  }
+}