BridgeJS: Fix closures with struct return #2621

Job	Run time
prettier	10s
format	31s
build-examples	20m 15s
check-bridgejs-generated	2m 52s
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	3m 8s
Test BridgeJS against Swift versions (swift:6.3, 603.0.0)	3m 8s
Build for native target (macos-15, Xcode_16.4)	2m 7s
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	2m 50s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	13m 48s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	12m 28s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	18m 37s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	13m 35s
deploy-examples	-1s
	1h 33m 28s

Provide feedback