**🚀 Enhancement**
- SRT and KTX codes are now completely internalized and renewed.
- You can **reserve, pay for, and refund** both purchased and non-purchased tickets for SRT and KTX.
- You can purchase **child, senior, and accessible** tickets for both SRT and KTX.
**🔧 Fixes**
- Fixed SRT refund issue for purchased tickets (38).
- Added Netfunnel key requirement for SRT (and KTX) (25, 26, 28).
- Resolved periodic login requirement for SRT (32).
- Handled SRT.reserve() retrieval error (35, 36).
- Ignores train seat availability when reserving KTX tickets (33).
- Fixed issue with checking reservations during boarding for SRT.