* Fixup typo
* Add new feature
* Add new TransactionError
* Add framework for checking account state before and after transaction processing
* Fail transactions that leave new rent-paying accounts
* Only check rent-state of writable tx accounts
* Review comments: combine process_result success behavior; log and metrics before feature activation
* Fix tests that assume rent-exempt accounts are okay
* Remove test no longer relevant
* Remove native/sysvar special case
* Move metrics submission to report legacy->legacy rent paying transitions as well
* Move test-validator to own module to reduce core dependencies
* Fix a few TestValidator paths
* Use solana_test_validator crate for solana_test_validator bin
* Move client int tests to separate crate
Co-authored-by: Tyera Eulberg <tyera@solana.com>