feat: add csrf to go web server

[takanome-dev]

What type of PR is this? (check all applicable)

• [x] 💡 Feature
• [ ] 🐛 Bug Fix
• [ ] 📝 Documentation Update
• [ ] 🎨 Style
• [ ] 🧑‍💻 Code Refactor
• [ ] 🔥 Performance Improvements
• [ ] ✅ Test
• [ ] 🤖 Build
• [ ] 🔁 CI
• [ ] ⏩ Revert

Description

This pr adds a CSRF protection(token) to the Go web server.

Related Tickets & Documents

Fixes #56

Mobile & Desktop Screenshots/Recordings

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