fix: content review - skills, project details, naming fixes

- Change PostgreSQL to MySQL in skills
- Add Nginx to infrastructure skills
- Remove No-ill PM from Experience (already in Projects)
- Add hongik.tolelom.xyz and docs links to Hongik project
- Add Unity client mention to One of the Plans
- Fix No-Ill → No-ill casing
- Fix About: game server instead of multiplayer server
- Fix No-ill description: development lead, not planning

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

data/sites.js

@@ -3,7 +3,7 @@ const sites = {
     { name: "Blog", url: "https://blog.tolelom.xyz", icon: "📝", description: "개인 블로그" },
     { name: "One of the Plans", url: "https://a301.tolelom.xyz", icon: "🎮", description: "MMORPG Unity 게임" },
     {
-      name: "No-Ill",
+      name: "No-ill",
       url: "https://no-ill.tolelom.xyz",
       icon: "🏥",
       description: "노인 낙상감지 · 외로움방지",