refactor: remove snippets feature and n8n project detection

- Remove snippets page, component, API route, Directus types, and setup script
- Remove snippets section from About.tsx (card, modal, state)
- Remove snippets link from 404 page, simplify layout
- Remove n8n Docker event and callback handler workflows (auto project detection)
- Remove Gitea runner setup and deploy scripts

lib/directus.ts

@@ -937,63 +937,6 @@ export async function getProjectBySlug(
   }
 }
 
-// Snippets Types
-export interface Snippet {
-  id: string;
-  title: string;
-  category: string;
-  code: string;
-  description: string;
-  language: string;
-}
-
-/**
- * Get Snippets from Directus
- */
-export async function getSnippets(limit = 10, featured?: boolean): Promise<Snippet[] | null> {
-  const filters = ['status: { _eq: "published" }'];
-  if (featured !== undefined) {
-    filters.push(`featured: { _eq: ${featured} }`);
-  }
-  const filterString = `filter: { _and: [{ ${filters.join(' }, { ')} }] }`;
-
-  const query = `
-    query {
-      snippets(
-        ${filterString}
-        limit: ${limit}
-      ) {
-        id
-        title
-        category
-        code
-        description
-        language
-      }
-    }
-  `;
-
-  try {
-    const result = await directusRequest(
-      '',
-      { body: { query } }
-    );
-
-    interface SnippetsResult {
-      snippets: Snippet[];
-    }
-    const snippets = (result as SnippetsResult | null)?.snippets;
-    if (!snippets || snippets.length === 0) {
-      return null;
-    }
-
-    return snippets;
-  } catch (_error) {
-    console.error('Failed to fetch snippets:', _error);
-    return null;
-  }
-}
-
 // ─── Hardcover → Directus sync helpers ───────────────────────────────────────
 
 export interface BookReviewCreate {