Add in-process FFI transport for Rust SDK #1696

Job	Run time
Rust SDK Bundled CLI Build (macos-latest)	3m 11s
Rust SDK Tests (macos-latest, inprocess)	12m 45s
Rust SDK Tests (ubuntu-latest, inprocess)	14m 18s
Rust SDK Tests (windows-latest, default)	12m 59s
Rust SDK Bundled CLI Build (windows-latest)	4m 4s
Rust SDK Tests (macos-latest, default)	7m 37s
Rust SDK Tests (ubuntu-latest, default)	9m 40s
Rust SDK Bundled CLI Build (ubuntu-latest)	2m 26s
	1h 7m 0s

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