refactor: upgrade ESLint 9→10 and simplify React lint toolchain

- Upgrade eslint and @eslint/js to v10
- Replace eslint-plugin-react-x + eslint-plugin-react-dom + eslint-plugin-react-hooks
  with unified @eslint-react/eslint-plugin
- Raise dev Node.js requirement to ^22.13.0 || >=24 (runtime packages unaffected)
- Add .npmrc with engine-strict=true
- Move all @eslint-react rule overrides to eslint.config.js,
  eliminating plugin-specific inline eslint-disable comments
- Fix real issues caught by new rules: useless assignments,
  leaked setTimeout, ref naming, useState setter naming

packages/extension/src/entrypoints/hub/App.tsx

@@ -133,7 +133,6 @@ export default function App() {
 					)}
 
 					{history.map((event, index) => (
-						// eslint-disable-next-line react-x/no-array-index-key
 						<EventCard key={index} event={event} />
 					))}
 

packages/extension/src/entrypoints/hub/hub-ws.ts

@@ -206,9 +206,9 @@ export function useHubWs(
 	const [wsState, setWsState] = useState<HubWsState>(() => (wsPort ? 'connecting' : 'disconnected'))
 	const hubWsRef = useRef<HubWs | null>(null)
 
-	const latest = useRef({ execute, stop, configure, config })
+	const latestRef = useRef({ execute, stop, configure, config })
 	useEffect(() => {
-		latest.current = { execute, stop, configure, config }
+		latestRef.current = { execute, stop, configure, config }
 	})
 
 	useEffect(() => {
@@ -218,14 +218,14 @@ export function useHubWs(
 			Number(wsPort),
 			{
 				onExecute: async (task, incomingConfig) => {
-					const { execute, configure, config } = latest.current
+					const { execute, configure, config } = latestRef.current
 					if (incomingConfig) {
 						await configure({ ...config, ...incomingConfig } as ExtConfig)
 					}
 					const result = await execute(task)
 					return { success: result.success, data: result.data }
 				},
-				onStop: () => latest.current.stop(),
+				onStop: () => latestRef.current.stop(),
 			},
 			setWsState
 		)

packages/extension/src/entrypoints/sidepanel/App.tsx

@@ -178,7 +178,6 @@ export default function App() {
 					{showEmptyState && <EmptyState />}
 
 					{history.map((event, index) => (
-						// eslint-disable-next-line react-x/no-array-index-key
 						<EventCard key={index} event={event} />
 					))}