docs(ticket-006): close completed delivery

[tom-sapletta-com]

Records exact-head Validator approval, merge evidence, and the final DONE state for ticket-006.

[ifuri-validator-agent]

Deterministic Validator approval for exact head 5bd267a78f998f31bd53e10277ab2ba7b898da72.

Ticket: ticket-006
Correlation ID: goal-pr-19-ticket-006-5bd267a7
Model: openrouter/z-ai/glm-5.2
Reviewed diff chunks: 1
Advisory LLM verdict: APPROVE
Advisory summary: Reviewed all 1 diff chunk(s). Documentation-only update marking ticket-006 as DONE. Adds delivery evidence (PR #16, approved head SHA, validator identity, merge commit) to the ticket README, AI codex logs, and changelog. TODO.md is updated consistently to reflect the completed state. No code changes, no security concerns. CI checks for Python 3.12 and 3.13 both pass.
Advisory findings: none
The LLM output above is advisory and was not used as the approval trust root.
Merge was not requested or performed.