feat: add JSON config module with load/save/defaults

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/data/config.ts

@@ -0,0 +1,48 @@
+import { readFileSync, writeFileSync, mkdirSync } from "node:fs";
+import { dirname } from "node:path";
+
+export interface BotConfig {
+  webPort: number;
+  locale: string;
+  theme: string;
+  commandPrefix: string;
+  commandAliases: Record<string, string>;
+  neteaseApiPort: number;
+  qqMusicApiPort: number;
+  adminPassword: string;
+  adminGroups: number[];
+  autoReturnDelay: number;
+  autoPauseOnEmpty: boolean;
+}
+
+export function getDefaultConfig(): BotConfig {
+  return {
+    webPort: 3000,
+    locale: "zh",
+    theme: "dark",
+    commandPrefix: "!",
+    commandAliases: { p: "play", s: "skip", n: "next" },
+    neteaseApiPort: 3001,
+    qqMusicApiPort: 3002,
+    adminPassword: "",
+    adminGroups: [],
+    autoReturnDelay: 300,
+    autoPauseOnEmpty: true,
+  };
+}
+
+export function loadConfig(path: string): BotConfig {
+  const defaults = getDefaultConfig();
+  try {
+    const raw = readFileSync(path, "utf-8");
+    const partial = JSON.parse(raw) as Partial<BotConfig>;
+    return { ...defaults, ...partial };
+  } catch {
+    return defaults;
+  }
+}
+
+export function saveConfig(path: string, config: BotConfig): void {
+  mkdirSync(dirname(path), { recursive: true });
+  writeFileSync(path, JSON.stringify(config, null, 2), "utf-8");
+}