refactor: 移除项目详情页硬编码的安装指南

移除了对所有带 GitHub 链接项目自动显示的通用安装命令（npm install），
现在安装说明应通过项目的 Markdown 内容字段自定义，更加灵活。

src/components/project/ProjectDetail.tsx

@@ -118,21 +118,6 @@ export async function ProjectDetail({ project, locale }: ProjectDetailProps) {
 
         {/* Full content with Markdown rendering */}
         {displayContent && <MarkdownContent content={displayContent} />}
-
-        {/* Installation section if GitHub link exists */}
-        {project.links.some((l) => l.type === 'GITHUB') && (
-          <>
-            <h3>{t('gettingStarted')}</h3>
-            <p>{t('installInstructions')}</p>
-            <pre className="bg-gray-100 dark:bg-gray-800 border border-black dark:border-gray-600 p-4 font-mono text-sm overflow-x-auto">
-              <code>{`git clone ${
-                project.links.find((l) => l.type === 'GITHUB')?.url || 'https://github.com/example/project'
-              }
-cd ${project.slug}
-npm install`}</code>
-            </pre>
-          </>
-        )}
       </article>
 
       {/* Share and Feedback Section - Temporarily disabled for debugging */}