feat(assets): 文件夹主题 - 新增多主题皮肤并同步主线

web/src/lib/canvas/canvas-folder-theme.ts

@@ -0,0 +1,23 @@
+import type { CanvasFolderTheme } from "@/types/canvas";
+
+export const CANVAS_FOLDER_THEME_OPTIONS: ReadonlyArray<{
+    key: CanvasFolderTheme;
+    label: string;
+    cover: string;
+}> = [
+    { key: "aurora", label: "赤蓝流光", cover: "/images/canvas/folder-default-cover.png" },
+    { key: "obsidian", label: "曜石银蓝", cover: "/images/canvas/folder-theme-obsidian.png" },
+    { key: "ember", label: "熔金赤焰", cover: "/images/canvas/folder-theme-ember.png" },
+    { key: "pearl", label: "珍珠薄雾", cover: "/images/canvas/folder-theme-pearl.png" },
+];
+
+export function resolveCanvasFolderTheme(value?: string): CanvasFolderTheme {
+    return CANVAS_FOLDER_THEME_OPTIONS.some((theme) => theme.key === value) ? value as CanvasFolderTheme : "aurora";
+}
+
+export function resolveCanvasFolderThemeCover(theme?: string, customCover?: string) {
+    const custom = customCover?.trim();
+    if (custom) return custom;
+    const resolved = resolveCanvasFolderTheme(theme);
+    return CANVAS_FOLDER_THEME_OPTIONS.find((item) => item.key === resolved)!.cover;
+}