xkernel v2.0.0: Invariant Deterministic Execution Kernel with Canonical Receipts

xkernel v2.0 is a minimal, invariant, deterministic execution kernel. The system defines a strict k=1 execution model with admissible steps,deterministic replay, boolean closure, and canonical hashing of bothexecutions and receipts. All verification is integrity-only and doesnot encode semantics beyond reproducibility. This release intentionally removes lenses, viewers, and simulationartifacts present in earlier experimental versions. xkernel v2.0defines a stable, auditable core suitable for cryptographic receipts,governance systems, and reproducible computation pipelines. Key features:- Deterministic execution with k = 1 step quantum- Admissibility-checked state transitions- Boolean closure via deterministic replay- Canonical JSON serialization- Content-addressed execution identifiers (xk:sha256)- Canonical receipt generation and verification (xr:sha256)- Strict CLI for validate, hash, receipt, verify, and receipt-hash- No embedded lenses, viewers, or domain semantics This release represents an invariant boundary and a semantic breakfrom all prior xkernel versions.