feat: Make models Sendable (#829) #3997

Job	Run time
apple-ci (macos-13, Xcode_15.2, platform=iOS Simulator,OS=17.2,name=iPhone 15)	10m 13s
linux-ci (5.9-amazonlinux2)	3m 45s
apple-ci (macos-13, Xcode_15.2, platform=tvOS Simulator,OS=17.2,name=Apple TV 4K (3rd generation)...	6m 55s
apple-downstream (macos-13, Xcode_15.2, platform=iOS Simulator,OS=17.2,name=iPhone 15)	12m 27s
linux-ci (5.9-focal)	3m 49s
apple-ci (macos-13, Xcode_15.2, platform=OS X)	5m 38s
apple-downstream (macos-13, Xcode_15.2, platform=tvOS Simulator,OS=17.2,name=Apple TV 4K (3rd gen...	9m 39s
linux-ci (6.0-amazonlinux2)	3m 58s
apple-ci (macos-14, Xcode_16.0, platform=iOS Simulator,OS=18.0,name=iPhone 15)	11m 7s
apple-downstream (macos-13, Xcode_15.2, platform=OS X)	9m 1s
linux-ci (6.0-jammy)	4m 0s
apple-ci (macos-14, Xcode_16.0, platform=tvOS Simulator,OS=18.0,name=Apple TV 4K (3rd generation)...	4m 24s
apple-downstream (macos-14, Xcode_16.0, platform=iOS Simulator,OS=18.0,name=iPhone 15)	10m 14s
apple-ci (macos-14, Xcode_16.0, platform=OS X)	4m 19s
apple-downstream (macos-14, Xcode_16.0, platform=tvOS Simulator,OS=18.0,name=Apple TV 4K (3rd gen...	7m 10s
linux-downstream (5.9-amazonlinux2)	4m 52s
apple-downstream (macos-14, Xcode_16.0, platform=OS X)	6m 54s
linux-downstream (5.9-focal)	5m 3s
linux-downstream (6.0-amazonlinux2)	5m 26s
linux-downstream (6.0-jammy)	5m 0s
	2h 13m 54s

Provide feedback