#421 Upgrade TUI graphics — better AI-generated ANSI or a Moebius hand-authored pipeline

Problem

The current ANSI-style graphics for ports, ships, and sectors in the tradewars TUI look basic compared to the original Tradewars, which had distinctly slick hand-drawn ANSI art. The gap is most visible in port character-art (12e89fc) and the per-player Blocky/Liney skins (db41bf3).

This codebase has two intentional skins (Blocky and Liney) — both must be preserved in any solution. See the project's TUI-skins guidance.

Proposed solution

Two directions, possibly both:

1. Better AI-generated ANSI. Improve the prompting / generation process so AI-authored scenes look closer to the original game's quality. Keep authorship in-tree.
2. Hand-authored pipeline via Moebius. Build a developer-centric workflow where I can design ANSI art in Moebius and have its output drop cleanly into the codebase. Moebius output (ANS / XBin / etc.) should be importable as scene assets without manual reformatting. The Blocky/Liney skin split must remain intact — likely meaning two variants per scene, or a skin-agnostic source format that renders to both.

Pick one or both; propose concrete next steps (file formats, asset directory layout, loader changes).

Alternatives

• Status quo (basic ANSI). Rejected: gap to original is the whole point of filing this.
• Replace ANSI with bitmap/sprite rendering. Rejected: TUI/terminal is the design.
• Import existing public-domain Tradewars ANSI assets. Worth considering only if licensing is clean.

Notes

This issue is the demo target for the new tradewars-lifecycle pipeline (@swamp/issue-lifecycle), so it'll get triaged + planned + iterated through that model.