docs: Add Realm ABI Specification #7672

Job	Run time
Run Main (autocounterd) / Go Build / generated	7s
Run Main (autocounterd) / Go Linter / lint	37s
Run Main (autocounterd) / Go Test / test	34s
Run Main (docker-integration) / Go Build / generated	3s
Run Main (docker-integration) / Go Linter / lint	5s
Run Main (docker-integration) / Go Test / test	16s
Run Main (genproto) / Go Build / generated	5s
Run Main (genproto) / Go Linter / lint	38s
Run Main (genproto) / Go Test / test	37s
Run Main (genstd) / Go Build / generated	11s
Run Main (genstd) / Go Linter / lint	17s
Run Main (genstd) / Go Test / test	33s
Run Main (goscan) / Go Build / generated	5s
Run Main (goscan) / Go Test / test	21s
Run Main (goscan) / Go Linter / lint	15s
Run Main (logos) / Go Build / generated	4s
Run Main (logos) / Go Linter / lint	25s
Run Main (logos) / Go Test / test	46s
Run Main (loop) / Go Build / generated	7s
Run Main (loop) / Go Linter / lint	33s
Run Main (loop) / Go Test / test	49s
	7m 28s

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