[philipgreat]

Closes #175.

Implements the accepted V1 context-bound Round-Trip Reference core for Java and aligns its tqr1 wire format with Rust.

• binds trusted Actor/Domain Root, service/environment, purpose/document, Aggregate revision, and entity type/ID/version
• uses AES-256-GCM, HKDF-SHA-256, 96-bit nonces, key rotation, expiry, and current authorization at issue/consume
• retains the exact shared Rust/Java deterministic golden vector
• covers RAW-01 through RAW-09 and removes the earlier weaker dual codec/raw fallback
• adds and verifies a framework-neutral runtime example

Evidence: examples/conformance/evidence/2026-09-27-context-bound-round-trip-reference.md.

Local verification: mvn clean verify (39/39 modules successful). No release is part of this PR.