feat(themes): Solarized and One theme plugins (#92)

Solarized Light/Dark and One Light/Dark ship as theme plugins (plugins/theme-solarized, plugins/theme-one) with complete UI tokens, editor schemes and terminal colours, and the original palettes' MIT notices. Installing a plugin now also copies its LICENSE/NOTICE/COPYING.

Theme handling that benefits every plugin theme:
- The last plugin theme is restored before first paint (splash, workbench); the native window background follows the theme.
- HSL / color-mix() / var() colours are resolved to RGB for native windows, the Settings window and Mermaid.
- Mermaid, the terminal and editor schemes follow switches between two themes of the same kind.
- An explicitly chosen editor scheme wins over a plugin theme's editor colours.

Supersedes #85.

Co-authored-by: bghtyu <[email protected]>
Claude-Session: https://claude.ai/code/session_01VUYsdXA2nkF5v6zsC93dpn

src/features/plugins/backend.ts

@@ -18,6 +18,8 @@ export interface PluginsBackend {
   runCommand(pluginId: string, commandId: string, arg: string | null): Promise<string | null>;
   setActiveFile(path: string | null): Promise<void>;
   setTheme(pluginId: string | null, themeId: string | null): Promise<ActiveTheme | null>;
+  /** The selected theme's resolved frame colour (`#rrggbb[aa]`), which new windows open in. */
+  setThemeFrame(color: string | null): Promise<void>;
   /** Folder picker; `null` when cancelled. */
   pickFolder(): Promise<string | null>;
   /** Subscribes to backend plugin events (this window only). */
@@ -40,6 +42,9 @@ export const tauriPluginsBackend: PluginsBackend = {
     await commands.pluginSetActiveFile(path);
   },
   setTheme: (pluginId, themeId) => call(commands.pluginSetTheme(pluginId, themeId)),
+  setThemeFrame: async (color) => {
+    await call(commands.pluginSetThemeFrame(color));
+  },
   pickFolder: async () => {
     const { open } = await import("@tauri-apps/plugin-dialog");
     const picked = await open({ directory: true, multiple: false, title: "Install Plugin from Disk" });
@@ -71,21 +76,38 @@ function ensureSubscribed() {
 // ---------------------------------------------------------------------------
 // Browser simulation: the bundled sample plugins, with `hello` implemented in JS.
 
-const SOLARIZED: ActiveTheme["theme"] = {
-  id: "solarized-dark",
-  name: "Solarized Dark",
-  kind: "dark",
-  tokens: {
-    "--bg-app": "#002b36",
-    "--bg-elev": "#03313c",
-    "--bg-popup": "#073642",
-    "--fg": "#93a1a1",
-    "--fg-strong": "#eee8d5",
-    "--accent": "#268bd2",
-    "--syn-keyword": "#859900",
-    "--syn-string": "#2aa198",
+const SOLARIZED: ActiveTheme["theme"][] = [
+  {
+    id: "solarized-light",
+    name: "Solarized Light",
+    kind: "light",
+    tokens: {
+      "--bg-app": "#fdf6e3",
+      "--bg-island": "#fdf6e3",
+      "--bg-frame": "#eee8d5",
+      "--bg-elev": "#eee8d5",
+      "--fg": "#657b83",
+      "--accent": "#268bd2",
+      "--syn-keyword": "#859900",
+      "--syn-string": "#2aa198",
+    },
   },
-};
+  {
+    id: "solarized-dark",
+    name: "Solarized Dark",
+    kind: "dark",
+    tokens: {
+      "--bg-app": "#002b36",
+      "--bg-island": "#002b36",
+      "--bg-frame": "#073642",
+      "--bg-elev": "#073642",
+      "--fg": "#839496",
+      "--accent": "#268bd2",
+      "--syn-keyword": "#859900",
+      "--syn-string": "#2aa198",
+    },
+  },
+];
 
 function samplePlugins(): PluginInfo[] {
   const base = {
@@ -118,14 +140,14 @@ function samplePlugins(): PluginInfo[] {
     },
     {
       ...base,
-      id: "theme-solarized-dark",
-      name: "Solarized Dark Theme",
+      id: "theme-solarized",
+      name: "Solarized Themes",
       version: "1.0.0",
-      description: "Ethan Schoonover's Solarized palette, dark variant.",
-      path: "~/Library/Application Support/ai.l0ng.openidea/plugins/theme-solarized-dark",
+      description: "Solarized Light and Solarized Dark: Ethan Schoonover's Solarized palette.",
+      path: "~/Library/Application Support/ai.l0ng.openidea/plugins/theme-solarized",
       status: "static",
       hasCode: false,
-      themes: [{ id: "solarized-dark", name: "Solarized Dark", kind: "dark" }],
+      themes: SOLARIZED.map(({ id, name, kind }) => ({ id, name, kind })),
     },
     {
       ...base,
@@ -179,8 +201,9 @@ export function createMemoryPluginsBackend(
   const activeTheme = (): ActiveTheme | null => {
     if (!theme) return null;
     const p = plugins.find((x) => x.id === theme?.pluginId);
-    if (!p?.enabled || theme.themeId !== SOLARIZED.id) return null;
-    return { pluginId: p.id, theme: SOLARIZED };
+    const t = SOLARIZED.find((x) => x.id === theme?.themeId);
+    if (!p?.enabled || !t) return null;
+    return { pluginId: p.id, theme: t };
   };
   return {
     list: async () => ({ plugins: plugins.map((p) => ({ ...p })), activeTheme: activeTheme() }),
@@ -237,6 +260,7 @@ export function createMemoryPluginsBackend(
       emit({ type: "themeChanged", theme: t });
       return t;
     },
+    setThemeFrame: async () => {},
     pickFolder: async () => null,
     onEvent: (handler) => {
       listeners.add(handler);