BridgeJS: Support throws and async for closures #2713

Job	Run time
build-examples	24m 59s
format	37s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	15m 25s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	13m 47s
check-bridgejs-generated	2m 56s
Build for native target (macos-15, Xcode_26.0.1)	2m 52s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	20m 29s
Test BridgeJS against Swift versions (swift:6.3, 603.0.0)	3m 11s
prettier	15s
deploy-examples	1s
	1h 24m 32s

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