feat: improve server management and refund display

Server Management:
- Fix /server command API auth (query param instead of header)
- Show server specs (vCPU/RAM/Bandwidth) in /server list
- Prevent AI from refusing server deletion based on expiration date
- Add explicit instructions in tool description and system prompt

Refund Display:
- Show before/after balance in server deletion refund message
- Format: 환불 전 잔액 → 환불 금액 → 환불 후 잔액

Other Changes:
- Add stopped status migration for server orders
- Clean up callback handler (remove deprecated code)
- Update constants and pattern utilities

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/utils/patterns.ts

@@ -13,7 +13,7 @@
 
 export const DOMAIN_PATTERNS = /도메인|네임서버|whois|dns|tld|등록|\.com|\.net|\.io|\.kr|\.org/i;
 export const DEPOSIT_PATTERNS = /입금|충전|잔액|계좌|예치금|송금|돈/i;
-export const SERVER_PATTERNS = /서버|VPS|클라우드|호스팅|인스턴스|linode|vultr/i;
+export const SERVER_PATTERNS = /서버|VPS|클라우드|호스팅|인스턴스|linode|vultr|\d+번\s*(?:시작|중지|정지|재시작|리셋|리부팅|삭제|해지)|#\d+\s*(?:시작|중지|정지|재시작|리셋|리부팅|삭제|해지)|reboot/i;
 export const TROUBLESHOOT_PATTERNS = /문제|에러|오류|안[돼되]|느려|트러블|장애|버그|실패|안\s*됨/i;
 export const WEATHER_PATTERNS = /날씨|기온|비|눈|맑|흐림|더워|추워/i;
 export const SEARCH_PATTERNS = /검색|찾아|뭐야|뉴스|최신/i;