Restructure docs into manual/development and add implementation docs (#94)

## Summary by Sourcery

Restructure documentation into separate manual and development sections,
introduce detailed internal implementation docs for auth/Java/mod
loaders, and update site navigation, landing page links, and MDX tooling
(Mermaid, card styling) to match the new structure and tech stack.

Enhancements:
- Enable Mermaid rendering support in the docs app and add a reusable
Mermaid React component.
- Refine Docs page rendering by customizing Card styling and removing
redundant in-page titles/descriptions rendered by the layout.
- Align docs source configuration and routing comments with the new
manual-based default paths.

Documentation:
- Split user-facing docs under a new manual section and move contributor
content into a dedicated development section for both English and
Chinese.
- Add comprehensive internal implementation documentation covering
authentication, Java management, mod loader/version merging, event bus,
and architecture patterns in both English and Chinese.
- Update existing feature docs (mod loaders, Java, authentication) and
getting-started/troubleshooting pages to be more conceptual, pointing to
implementation docs for technical details.
- Refresh architecture docs to reflect the React/Zustand frontend stack
and add Mermaid-based architecture diagrams.
- Adjust navigation labels, home-page CTAs, and doc links to target the
new manual/development structure and routes.

---------

Co-authored-by: 简律纯 <i@jyunko.cn>

1 files changed, 6 insertions, 1 deletions

diff --git a/packages/docs/source.config.ts b/packages/docs/source.config.ts
index d67a91b..7880853 100644
--- a/packages/docs/source.config.ts
+++ b/packages/docs/source.config.ts
@@ -1,7 +1,12 @@
 import { defineConfig, defineDocs } from 'fumadocs-mdx/config';
+import { remarkMdxMermaid } from 'fumadocs-core/mdx-plugins';
 
 export const docs = defineDocs({
   dir: 'content',
 });
 
-export default defineConfig();
+export default defineConfig({
+  mdxOptions: {
+    remarkPlugins: [remarkMdxMermaid],
+  },
+});