[BLCCoreStudio]

Summary

Upgrades tool/opentofu from schema v2 into a schema-v3 deep technical reference centered on OpenTofu's infrastructure lifecycle model, provider compatibility, state ownership, native state/plan encryption, and Terraform migration boundaries.

Changes

• explain OpenTofu Core, provider plugins, dependency-aware evaluation, resource addresses, count/for_each, state, backends, locking, plan/apply, drift, and modules
• document the Public OpenTofu Registry and provider/module supply-chain boundaries
• cover .terraform.lock.hcl, provider pinning, aliases, state lineage/serial safeguards, state recovery, and CI/CD single-writer semantics
• deeply cover native state and plan encryption: key providers, KMS boundaries, AES-GCM, migration/fallback, rotation, replay limits, and key-loss disaster recovery
• document v1.x compatibility promises, Terraform migration workflow, version-specific migration paths, registry/tooling assumptions, cross-state migration, and portability trade-offs
• distinguish .tf/.tofu format choices and the impact of OpenTofu-specific language evolution on bidirectional portability
• add PR threat modeling, provider/module supply-chain guidance, state partitioning, Kubernetes ownership boundaries, failure modes, debugging, operational checklists, and learning path
• verify the canonical MPL-2.0 license and document Terraform as the closest indexed alternative
• add Technology Universe coverage metadata and typed relationships to Terraform and Kubernetes

Quality bar

The module keeps the shared Terraform/OpenTofu mental model where it is genuinely compatible while making governance, licensing, registry, encryption, migration, and future divergence explicit instead of assuming the implementations are interchangeable forever.