feat(themes): swap Moonlit Bloom for Crystal Nocturne, sort built-ins by colour family

Crystal Nocturne (royal sapphire + electric magenta on obsidian, by
CRYSTALLITE) replaces Moonlit Bloom in the built-in roster. The same
chat-channel tinting convention applies: sapphire-blue identity on
party/team channels, accent-magenta on tells, and an alternating
mint/yellow/peach palette across the eight linkshell slots so each
LS stays individually distinguishable on the dark obsidian background.

Users who had Moonlit Bloom selected fall back to the default Hellion
Arctic on the first plugin load. A custom JSON copy of Moonlit Bloom
dropped into pluginConfigs/HellionChat/themes/ keeps working as a
user theme.

Plus a cosmetic re-sort of the registry: insertion order now drives a
deliberate Theme-Picker grid layout (3 columns) — blue family in row 1,
purple to magenta in row 2, green/warm/classic in row 3, Synthwave
Sunset alone in row 4 as a retro bonus.

README.md

@@ -102,7 +102,7 @@ Hellion Chat is developed under **Hellion Forge**, the specialized modding and p
 #### Custom Themes (v1.1.0)
 
 HellionChat ships a theme engine with ten built-in themes (Hellion Arctic, Hellion Spectrum, Chat 2 Classic, Event
-Horizon, Moonlit Bloom, Mint Grove, Night Blue, Indigo Violet, Forge Merchantman, Synthwave Sunset) and a JSON-based
+Horizon, Crystal Nocturne, Mint Grove, Night Blue, Indigo Violet, Forge Merchantman, Synthwave Sunset) and a JSON-based
 authoring format for custom themes. Schema and step-by-step guide in
 [`docs/THEME-AUTHORING.md`](docs/THEME-AUTHORING.md). Hellion Spectrum is Deuteranopia/Protanopia-safe (red-green color
 blindness) based on the Wong/Okabe-Ito palette.