[BridgeJS] Support @JS var declarations for global scope imports #1920

Job	Run time
Build for native target (macos-15, Xcode_16.4)	2m 24s
build-examples	43m 3s
format	33s
check-bridgejs-generated	2m 53s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	16m 53s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	13m 3s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	13m 8s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	13m 42s
deploy-examples	0s
	1h 45m 39s

Provide feedback