BridgeJS: Unify optional stack encoding to presence-flag form #140

Job	Run time
prettier	13s
format	48s
check-bridgejs-generated	3m 35s
Test BridgeJS against Swift versions (swift:6.3, 603.0.0)	3m 34s
Build for native target (macos-15, Xcode_26.0.1)	2m 50s
Build and Test (ubuntu-24.04, https://download.swift.org/development/ubuntu2404/swift-DEVELOPMENT...	12m 50s
Build and Test (ubuntu-24.04, https://download.swift.org/swift-6.3-branch/ubuntu2404/swift-6.3-DE...	12m 51s
build-examples (ActorOnWebWorker)	8m 8s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	12m 52s
build-examples (Multithreading)	9m 50s
build-examples (OffscrenCanvas)	10m 12s
build-examples (Embedded)	9m 57s
build-examples (Basic)	10m 55s
build-examples (PlayBridgeJS)	10m 33s
build-examples-deploy	0s
deploy-examples	0s
	1h 49m 8s

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