feat: turn model history into a playable archive

[BrickerP]

Summary

• Turn focused model history into an SVG world generated from the existing daily series.
• Add deterministic, history-derived Run Signatures, day URL state, and one native timeline slider.
• Remove the old Run Stage, Replay, and Archive paths; update the creative docs and focused interaction tests.

Data & accessibility

• Collection and token, cost, and cache accounting remain unchanged.
• Missing model attribution stays unavailable rather than being inferred.
• The experience keeps one native range control, an exact-data table, and reduced-motion behavior.

Verification

• Static reviews and diff checks passed.
• Per repository policy, no local build or test run was performed; remote CI is authoritative.