- RESERVED_DEPLOYMENT_PROGRAM_ACCOUNT_ID: restore the SHA256 derivation
docstring that explains the constant instead of leaving it as an opaque
byte array, and switch the array itself to a hex literal (hex-literal,
already a workspace dependency) for readability.
- Rename the loader/loader_core crate to program_loader/program_loader_core
to disambiguate it, across the directory, package name, workspace
members/dependency alias, both dependent crates, and every call site.