feat(阶段3): oj 侧端点铺开（基线提交，未经评审）

由外部 agent (Codex) 在本会话额度中断期间完成。原样提交作为基线，
后续修复单独成 commit，便于区分与回退。

覆盖 oj 侧 65 个端点，新增 9 组路由（account/achievement/ai/classroom/
content/contest/flowchart/problemset/site）与对应 Zod 契约。

已核验：tsc --noEmit 退出码 0；API 可启动；/api/problems 返回真实数据；
judge 与 flowchart worker 均 ready。
未核验：权限边界与数据泄露，评审进行中。

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

apps/api/src/services/options.ts

@@ -0,0 +1,38 @@
+import { inArray } from "drizzle-orm"
+
+import { db, schema } from "../db"
+
+export const websiteOptionDefaults = {
+  website_base_url: "http://127.0.0.1",
+  website_name: "Online Judge",
+  website_name_shortcut: "oj",
+  website_footer: "Online Judge Footer",
+  allow_register: true,
+  submission_list_show_all: true,
+  class_list: [] as string[],
+  enable_maxkb: true,
+}
+
+export async function getOptions<const T extends readonly string[]>(keys: T) {
+  const rows = await db
+    .select({ key: schema.optionsSysoptions.key, value: schema.optionsSysoptions.value })
+    .from(schema.optionsSysoptions)
+    .where(inArray(schema.optionsSysoptions.key, [...keys]))
+  return Object.fromEntries(rows.map((row) => [row.key, row.value])) as Record<T[number], unknown>
+}
+
+export async function getWebsiteOptions() {
+  const keys = Object.keys(websiteOptionDefaults) as Array<keyof typeof websiteOptionDefaults>
+  const values = await getOptions(keys)
+  return Object.fromEntries(
+    keys.map((key) => [key, values[key] ?? websiteOptionDefaults[key]]),
+  ) as typeof websiteOptionDefaults
+}
+
+export async function getBooleanOption(
+  key: keyof typeof websiteOptionDefaults,
+  fallback: boolean,
+) {
+  const values = await getOptions([key])
+  return typeof values[key] === "boolean" ? values[key] : fallback
+}