fix(ui): refresh LOCAL SYSTEM after a jump instead of waiting for a page reload (#30)

WorldMapPanel owns the world state and applied the /api/jump response
locally, so MissionControl's lifted /api/system state (LOCAL SYSTEM tab,
CARGO HOLD, SECTOR row) stayed on the previous system until a full refresh.
The panel now takes an onJumped callback that MissionControl wires to an
/api/system refetch after every successful jump.

components/mission-control.tsx

@@ -1,6 +1,6 @@
 'use client'
 
-import { useEffect, useState } from 'react'
+import { useCallback, useEffect, useState } from 'react'
 import { Badge } from '@/components/ui/badge'
 import { Panel, PanelContent, PanelHeader, PanelTitle } from '@/components/ui/panel'
 import { Progress } from '@/components/ui/progress'
@@ -112,6 +112,19 @@ export function MissionControl() {
     if (stored && TAB_IDS.includes(stored)) setActiveTab(stored)
   }, [])
 
+  // #30 — re-fetch /api/system after a jump: WorldMapPanel owns the world state, so without this
+  // the lifted system state stays on the previous system until a page refresh. Same failure
+  // policy as the mount fetch — keep the old state on error.
+  const refreshSystem = useCallback(() => {
+    fetch('/api/system')
+      .then(async (res) => {
+        if (!res.ok) throw new Error(`HTTP ${res.status}`)
+        return (await res.json()) as SystemState
+      })
+      .then((s) => setSystem(s))
+      .catch(() => {})
+  }, [])
+
   const timeStr = new Date().toLocaleTimeString('en-GB', { hour12: false })
 
   // Slugs of the researched techs — drives the effective caps + build gates in the SHIP SYSTEMS
@@ -395,7 +408,7 @@ export function MissionControl() {
 
                   {/* WORLD MAP TAB — live data from /api/world */}
                   <TabsContent value="world-map" style={{ margin: 0, padding: '1rem' }}>
-                    <WorldMapPanel height={380} />
+                    <WorldMapPanel height={380} onJumped={refreshSystem} />
                   </TabsContent>
 
                   {/* LOCAL SYSTEM TAB — live data (state owned by MissionControl; scans report up) */}

components/world-map.tsx

@@ -11,9 +11,10 @@ import type { WorldState } from '@/lib/game/save'
 
 interface WorldMapPanelProps {
   height?: number
+  onJumped?: () => void // #30 — let the parent refresh /api/system after a successful jump
 }
 
-export function WorldMapPanel({ height = 380 }: WorldMapPanelProps) {
+export function WorldMapPanel({ height = 380, onJumped }: WorldMapPanelProps) {
   const [world, setWorld] = useState<WorldState | null>(null)
   const [error, setError] = useState<string | null>(null)
   const [jumpingId, setJumpingId] = useState<number | null>(null)
@@ -47,12 +48,13 @@ export function WorldMapPanel({ height = 380 }: WorldMapPanelProps) {
       const body = (await res.json()) as WorldState & { error?: string }
       if (!res.ok) throw new Error(body.error ?? `HTTP ${res.status}`)
       setWorld(body) // fresh state straight from the response — no refetch needed
+      onJumped?.() // #30 — parent re-fetches /api/system (LOCAL SYSTEM + CARGO HOLD mirror it)
     } catch (err: unknown) {
       setError(err instanceof Error ? err.message : String(err))
     } finally {
       setJumpingId(null)
     }
-  }, [])
+  }, [onJumped])
 
   if (error && !world) {
     return (