v1.2.0 - UI polish + skill slash-commands

Polishes the OlmoEarth Agent web UI and adds in-chat skill slash-commands.

New

• In-chat skill slash-commands — type / in the composer to call a specific skill directly (like Claude Code's /commands): a filterable menu of the 16 skills, arrow-nav + Enter/click to select. The brief is then routed to that skill (the displayed message stays as you typed it).

Fixed (from a multi-agent doc↔code↔architecture audit — every finding adversarially verified, 26 raw → 7 confirmed)

• README: "18-skill catalog" → 16; documented the 5 omitted js/ modules and the 7 omitted bridge endpoints.
• prefers-reduced-motion now covers the remaining animations (modal/detail entry, typing dots, caret, tool-call pulse, flash-glow).
• Added a --mint-hi design token; the difference-scan button hover uses it instead of a hardcoded color.

Also shipped in this line (the UI-polish pass)

Loading & busy states · difference-map radar scan · in-conversation result block · consecutive-workflow indicator · reproducible difference scan (retries flaky pixel fetches so the same pair gives the same numbers) · trajectory-chart fix · de-duplicated compare A/B legend · feature-showcase demo (webui/demo/record_showcase.py).