Add TKQR1: Animated-QR Air-Gap Transport for Arbitrary Payloads

[RexStarBSV]

This pull request:

Proposes a new standard by creating a new markdown file in the appropriate directory and requests discussion and assignment of a BRC number

Summary

This proposes TKQR1, a text framing that carries an arbitrary byte string across an optical air gap as a sequence of QR codes and reassembles it with integrity and set-consistency checks. Each frame is one line of US-ASCII: a fixed prefix, a 64-bit truncated SHA-256 payload tag, a sequence number, a frame total, and a base64url slice of the payload. The shared tag binds every frame to one payload, so a collector rejects frames from a different or stale stream, refuses to emit until the set is complete, and re-verifies the full payload hash before returning bytes. BSV currently has no standard for animated-QR transport; the closest prior art is BC-UR on BTC, which shares no wire format. The spec is grounded in a working reference implementation, two byte-compatible ports validated against a shared vector file, and is written so a second implementer can build an interoperable version from the Specification and Test Vectors alone.

Validation

• Single new file; no index files touched, following the pattern of merged PR Standard for single-use signed auth proofs #156.
• The test vectors in the document reproduce exactly against both reference ports.