fix(lint): replace explicit-any types + unused-expressions ternaries

Five files, all stylistic:

- useFlowPilotSession.ts: typed the axios error shape with a narrow
  inline type instead of \`as any\`.
- FlowPilotSessionPage.tsx: same — typed location.state once, then
  destructured.
- ScriptBuilderTab.tsx: handleViewScript was a placeholder no-op;
  declared the args properly with \`void script; void filename\` so the
  signature matches ScriptBuilderChatProps without no-unused-vars
  firing.
- TicketsPage.tsx: replaced 8 ternaries-as-statements (\`x ? f() : g()\`)
  with proper if/else blocks. Same control flow, satisfies
  no-unused-expressions, and reads better in the URL-param update paths.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

frontend/src/pages/FlowPilotSessionPage.tsx

@@ -19,8 +19,9 @@ export default function FlowPilotSessionPage() {
   const navigate = useNavigate()
   const location = useLocation()
   const prefill = (location.state as { prefill?: string } | null)?.prefill || ''
-  const psaTicketId = (location.state as any)?.psaTicketId as string | undefined
-  const psaTicket = (location.state as any)?.psaTicket as PSATicketInfo | undefined
+  const locationState = location.state as { psaTicketId?: string; psaTicket?: PSATicketInfo } | null
+  const psaTicketId = locationState?.psaTicketId
+  const psaTicket = locationState?.psaTicket
   const isPickup = searchParams.get('pickup') === 'true'
   const fp = useFlowPilotSession()
   const branching = useBranching()