The root package becomes a virtual workspace: `crates/ecr` holds the
library (package name `ecr`) and `crates/ecr-cli` the command line
front-end, which keeps installing the `ecr` binary. No behavior change.
The library must not depend on CLI types, so mount::setup_mounts now
takes the `no_bind` flag instead of a `&Args`.
- Create unified Arch enum in utils.rs with methods for all naming conventions
- Replace 5 duplicate architecture mapping functions with single source of truth
- Add memory string validation for QEMU
- Add KVM capability verification via ioctl
- Fix TOCTOU race in resolv.conf writing using O_EXCL
- Extract magic numbers to named constants
- Use constants for stack size, buffer sizes, hostname entropy
vhaudiquet