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, 3 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index 5d6d0f3..1419805 100644
--- a/.gitignore
+++ b/.gitignore
@@ -31,3 +31,6 @@ artifacts/
 
 # AUR Release
 release/
+
+# claude code
+.claude/