fix: 6 integration audit fixes — ticket filter, admin nav, FK scope, debounce, error messages

- Fix AISession.ticket_id → psa_ticket_id in list_sessions filter query
- Add Gallery nav item (LayoutGrid icon) to AdminSidebar navItems array
- Remove ForeignKey from FileUpload.session_id (Python model) + migration b8d2f4a6c091 to drop DB constraint, allowing column to reference either session type
- Add 400ms debounce on AI session search input in SessionHistoryPage (aiSearchInput state + useRef timeout pattern)
- Show friendly 503 error message in RichTextInput upload error handler (both initial upload and retry paths)
- Add overflow-x-auto to FlowPilotAnalyticsPage tab bar container

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/FlowPilotAnalyticsPage.tsx

@@ -189,7 +189,7 @@ export default function FlowPilotAnalyticsPage() {
       </div>
 
       {/* Tab bar */}
-      <div className="flex gap-1 border-b border-border">
+      <div className="flex gap-1 border-b border-border overflow-x-auto">
         {TABS.map((tab) => (
           <button
             key={tab.id}

frontend/src/pages/SessionHistoryPage.tsx

@@ -25,6 +25,8 @@ export function SessionHistoryPage() {
   const [sessionType, setSessionType] = useState<'flow' | 'ai'>('flow')
   const [aiSessions, setAiSessions] = useState<AISessionSummary[]>([])
   const [aiLoading, setAiLoading] = useState(false)
+  const [aiSearchInput, setAiSearchInput] = useState('')
+  const aiSearchTimeout = useRef<ReturnType<typeof setTimeout> | undefined>(undefined)
   const [aiFilters, setAiFilters] = useState({
     q: '',
     problem_domain: '',
@@ -67,6 +69,15 @@ export function SessionHistoryPage() {
     }
   })
 
+  // Debounce AI search input → aiFilters.q
+  useEffect(() => {
+    if (aiSearchTimeout.current) clearTimeout(aiSearchTimeout.current)
+    aiSearchTimeout.current = setTimeout(() => {
+      setAiFilters(prev => ({ ...prev, q: aiSearchInput }))
+    }, 400)
+    return () => { if (aiSearchTimeout.current) clearTimeout(aiSearchTimeout.current) }
+  }, [aiSearchInput])
+
   // Load trees for filter dropdown
   useEffect(() => {
     const loadTrees = async () => {
@@ -324,8 +335,8 @@ export function SessionHistoryPage() {
                 <Search className="absolute left-2.5 top-1/2 -translate-y-1/2 h-3.5 w-3.5 text-muted-foreground pointer-events-none" />
                 <input
                   type="text"
-                  value={aiFilters.q}
-                  onChange={(e) => setAiFilters((f) => ({ ...f, q: e.target.value }))}
+                  value={aiSearchInput}
+                  onChange={(e) => setAiSearchInput(e.target.value)}
                   placeholder="Search sessions..."
                   className="w-full rounded-lg border border-border bg-card pl-8 pr-3 py-1.5 text-sm text-foreground placeholder:text-muted-foreground focus:border-[rgba(6,182,212,0.3)] focus:outline-none"
                 />
@@ -389,9 +400,12 @@ export function SessionHistoryPage() {
               </div>
 
               {/* Clear filters */}
-              {(aiFilters.q || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to) && (
+              {(aiSearchInput || aiFilters.q || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to) && (
                 <button
-                  onClick={() => setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })}
+                  onClick={() => {
+                    setAiSearchInput('')
+                    setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
+                  }}
                   className="text-xs text-muted-foreground hover:text-foreground transition-colors"
                 >
                   Clear
@@ -405,13 +419,16 @@ export function SessionHistoryPage() {
               <Spinner />
             </div>
           ) : aiSessions.length === 0 ? (
-            (aiFilters.q || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to) ? (
+            (aiSearchInput || aiFilters.q || aiFilters.problem_domain || aiFilters.confidence_tier || aiFilters.date_from || aiFilters.date_to) ? (
               <EmptyState
                 title="No sessions match your filters"
                 description="Try adjusting your search or filters."
                 action={
                   <button
-                    onClick={() => setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })}
+                    onClick={() => {
+                      setAiSearchInput('')
+                      setAiFilters({ q: '', problem_domain: '', confidence_tier: '', date_from: '', date_to: '' })
+                    }}
                     className="text-foreground hover:underline text-sm"
                   >
                     Clear all filters