Embedded: Swift SDK now passes the `-Xcc -D__EMBEDDED_SWIFT__` #1600

Job	Run time
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.1-release/ubuntu2204/swift-6.1-R...	2m 51s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	2m 52s
Build for native target (macos-15, Xcode_16.4)	34s
format	32s
Build and Test (ubuntu-22.04, https://download.swift.org/development/ubuntu2204/swift-DEVELOPMENT...	2m 52s
build-examples	11m 50s
Build and Test (ubuntu-22.04, https://download.swift.org/swift-6.0.2-release/ubuntu2204/swift-6.0...	2m 36s
deploy-examples	0s
	24m 7s

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