BridgeJS: Add `JSTypedClosure` API #2125

Job	Run time
Test BridgeJS against Swift versions (swift:6.2, 602.0.0)	3m 27s
check-bridgejs-generated	2m 42s
format	37s
build-examples	17m 52s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	12m 8s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	13m 36s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	17m 21s
Build for native target (macos-15, Xcode_16.4)	3m 31s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	12m 55s
Test BridgeJS against Swift versions (swift:6.1.2, 601.0.0)	2m 46s
deploy-examples	0s
	1h 26m 55s

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