v0.2.2 — MAT- prefix enforced; all examples updated to v0.2.0

Fixed

• MaterialDNA `id` pattern now requires `MAT-` prefix (`^MAT-[A-Z]{2}-[A-Z]{3}-\d{4}-[A-Z]+-[A-Z0-9]{6,}$`) — consistent with spec and symmetric with ProductDNA's `PRD-` prefix
• Updated schemas: `offer`, `match`, `transfer`, `material-status`, `transaction`, `loopcoin`, `product-dna` — all `material_id` / `material_ref` / `material_ids` patterns now require `MAT-` prefix
• All 15 example payloads updated: `schema_version: "0.2.0"`, `@context: loop-v0.2.0.jsonld`, and MaterialDNA ID fields prefixed with `MAT-`

Changed

• `SPECIFICATION.md` §3.6 added: entity status-transition reference table (Offer, Match, Transfer, MaterialStatusUpdate, Transaction)

LOOP v0.2.1 — ProductDNA & Spec Expansion

Added

• ProductDNA schema: a new DPP-aligned product-level entity that encapsulates category, condition, manufacturer, lifecycle stage, and references to MaterialDNA records — enabling product-level digital passports alongside material-level data.
• §2.1 canonical key concept definitions: the specification now carries authoritative definitions for LOOP, MaterialDNA, ProductDNA, LoopCoin, LoopSignal, and LoopCost in a dedicated section.
• Mermaid architecture diagram in the specification with MAT- prefix notation for MaterialDNA identifiers, plus a regulatory compatibility roadmap covering ESPR, UNTP, and Germany NKWS.
• Glossary expansion with canonical term definitions for all core protocol concepts.

Changed

• Specification TOC expanded with sub-items for §3.5 and §4.5.
• §13.1 reframed to surface ProductDNA alongside MaterialDNA in the Abstract and Core Components sections.
• Protocol contract documentation aligned to v0.2.0 interop requirements.

Maintenance

• Upgraded Contributor Covenant to v3.0 and replaced personal contact with org identity (dev@mycel-ai.de).
• Updated ajv to 8.20.0.

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Interop baseline: LOOP v0.2.0 JSON-LD context and schemas remain the active interop baseline. v0.2.1 is a spec and schema additive patch — no breaking changes to v0.2.0 payloads.