Set data-bs-theme based on the presence of "dark" in theme name (#2638)

src/assets/css/themes/i386-dark.scss

@@ -1,4 +1,4 @@
-@import "variables.i386";
+@import "variables.i386-dark";
 @import "../../../../node_modules/bootstrap/scss/bootstrap";
 
 .btn-outline-secondary {

src/server/utils/build-themes-list.ts

@@ -14,7 +14,7 @@ const themes: ReadonlyArray<string> = [
   "litely-compact",
   "vaporwave-dark",
   "vaporwave-light",
-  "i386",
+  "i386-dark",
 ];
 
 export async function buildThemeList(): Promise<ReadonlyArray<string>> {

src/shared/utils/browser/data-bs-theme.ts

@@ -9,15 +9,7 @@ export default function dataBsTheme(siteResOrTheme?: GetSiteResponse | string) {
         siteResOrTheme?.site_view.local_site.default_theme ??
         "browser");
 
-  return (isDark() && theme === "browser") ||
-    [
-      "darkly",
-      "darkly-red",
-      "darkly-pureblack",
-      "darkly-compact",
-      "i386",
-      "vaporwave-dark",
-    ].includes(theme)
+  return (isDark() && theme === "browser") || theme.includes("dark")
     ? "dark"
     : "light";
 }