Refactor documentation structure and dependencies for migration to Fumadocs

- Updated `.gitignore` to include new build and generated content directories.
- Removed outdated Mintlify configuration files and documentation.
- Introduced new `MIGRATION.md` to outline the transition from Mintlify to Fumadocs.
- Added `mdx-components.tsx` for MDX component configuration and compatibility.
- Updated `package.json` and `next.config.mjs` for new dependencies and Next.js configuration.
- Created `source.config.ts` for content source configuration.
- Added OpenAPI specification in `openapi.json` for API documentation.
- Removed legacy files and adjusted project structure to align with Fumadocs conventions.

docs/app/docs/[[...slug]]/page.tsx

@@ -0,0 +1,55 @@
+import { getPageImage, source } from '@/lib/source';
+import {
+  DocsBody,
+  DocsDescription,
+  DocsPage,
+  DocsTitle,
+} from 'fumadocs-ui/page';
+import { notFound } from 'next/navigation';
+import { getMDXComponents } from '@/mdx-components';
+import type { Metadata } from 'next';
+import { createRelativeLink } from 'fumadocs-ui/mdx';
+import { APIPage } from '@/components/api-page';
+
+export default async function Page(props: PageProps<'/docs/[[...slug]]'>) {
+  const params = await props.params;
+  const page = source.getPage(params.slug);
+  if (!page) notFound();
+
+  const MDX = page.data.body;
+
+  return (
+    <DocsPage toc={page.data.toc} full={page.data.full}>
+      <DocsTitle>{page.data.title}</DocsTitle>
+      <DocsDescription>{page.data.description}</DocsDescription>
+      <DocsBody>
+        <MDX
+          components={getMDXComponents({
+            // this allows you to link to other pages with relative file paths
+            a: createRelativeLink(source, page),
+          })}
+        />
+      </DocsBody>
+    </DocsPage>
+  );
+}
+
+export async function generateStaticParams() {
+  return source.generateParams();
+}
+
+export async function generateMetadata(
+  props: PageProps<'/docs/[[...slug]]'>,
+): Promise<Metadata> {
+  const params = await props.params;
+  const page = source.getPage(params.slug);
+  if (!page) notFound();
+
+  return {
+    title: page.data.title,
+    description: page.data.description,
+    openGraph: {
+      images: getPageImage(page).url,
+    },
+  };
+}

docs/app/docs/layout.tsx

@@ -0,0 +1,11 @@
+import { source } from '@/lib/source';
+import { DocsLayout } from 'fumadocs-ui/layouts/docs';
+import { baseOptions } from '@/lib/layout.shared';
+
+export default function Layout({ children }: LayoutProps<'/docs'>) {
+  return (
+    <DocsLayout tree={source.pageTree} {...baseOptions()}>
+      {children}
+    </DocsLayout>
+  );
+}