Update navigation in SubmissionDetailsPage to include userId in URL if available; initialize selectedUserId in SubmissionsPage from search parameters for improved user experience.

src/pages/submissions/SubmissionDetailsPage.tsx

@@ -24,8 +24,12 @@ export const SubmissionDetailsPage: React.FC = () => {
   const submission = submissions?.find((s) => s.id === submissionId)
 
   const handleBack = () => {
+    if (userId) {
+      navigate(`${URLs.submissions}?userId=${encodeURIComponent(userId)}`)
+    } else {
       navigate(URLs.submissions)
     }
+  }
 
   if (isLoading) {
     return <LoadingSpinner message={t('challenge.admin.submissions.loading')} />

src/pages/submissions/SubmissionsPage.tsx

@@ -1,6 +1,6 @@
 import React, { useState } from 'react'
 import { useTranslation } from 'react-i18next'
-import { useNavigate } from 'react-router-dom'
+import { useNavigate, useSearchParams } from 'react-router-dom'
 import {
   Box,
   Heading,
@@ -32,12 +32,14 @@ import type {
 export const SubmissionsPage: React.FC = () => {
   const { t } = useTranslation()
   const navigate = useNavigate()
+  const [searchParams] = useSearchParams()
+  const initialUserId = searchParams.get('userId')
   const { data: stats, isLoading: isStatsLoading, error: statsError, refetch: refetchStats } =
     useGetSystemStatsV2Query(undefined)
 
   const [searchQuery, setSearchQuery] = useState('')
   const [statusFilter, setStatusFilter] = useState<SubmissionStatus | 'all'>('all')
-  const [selectedUserId, setSelectedUserId] = useState<string | null>(null)
+  const [selectedUserId, setSelectedUserId] = useState<string | null>(initialUserId)
 
   const {
     data: submissions,