Every other background reads as a place or a material — Violet, Nebula,
Abyss, Ember, Moss, Graphite, Holo, Sunset, Bloom, Dawn, Mint, Opal — and
"OLED" was a spec sheet sitting among them, naming the panel it suits rather
than what it looks like. It looks like black with a thin violet corona at one
corner, which is an eclipse, and that puts it beside Nebula and Abyss.
The ID stays "oled" in all three clients: it is the stored ui_palette value
AND the cross-client key, so renaming it would orphan every saved choice and
silently desync Apple, Android and the console UI. Only the label moved. No
test or doc pinned the old string.
Palette tests pass; macOS builds.
enricobuehler
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