feat: KRW 가격 지원 및 GPU/G8/VPU 인스턴스 추가

## KRW 가격 기능
- pricing 테이블에 hourly_price_krw, monthly_price_krw 컬럼 추가
- 부가세 10% + 영업이익 10% + 환율 적용 (기본 1450원)
- 시간당: 1원 단위 반올림 (최소 1원)
- 월간: 100원 단위 반올림 (최소 100원)
- 환율/부가세/영업이익률 환경변수로 분리 (배포 없이 변경 가능)

## GPU/G8/VPU 인스턴스 지원
- gpu_instances, gpu_pricing 테이블 추가
- g8_instances, g8_pricing 테이블 추가
- vpu_instances, vpu_pricing 테이블 추가
- Linode/Vultr 커넥터에 GPU 동기화 로직 추가

## 환경변수 추가
- KRW_EXCHANGE_RATE: 환율 (기본 1450)
- KRW_VAT_RATE: 부가세율 (기본 1.1)
- KRW_MARKUP_RATE: 영업이익률 (기본 1.1)

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

src/constants.ts

@@ -176,6 +176,7 @@ export const CORS = {
   ALLOWED_ORIGINS: [
     'https://anvil.it.com',
     'https://cloud.anvil.it.com',
+    'https://hosting.anvil.it.com',
     'http://localhost:3000', // DEVELOPMENT ONLY - exclude in production
   ] as string[],
   /** Max age for CORS preflight cache (24 hours) */
@@ -223,3 +224,90 @@ export const REQUEST_LIMITS = {
   /** Maximum request body size in bytes (10KB) */
   MAX_BODY_SIZE: 10 * 1024,
 } as const;
+
+// ============================================================
+// KRW Pricing Configuration
+// ============================================================
+
+/**
+ * Default KRW (Korean Won) pricing configuration
+ *
+ * These defaults are used when environment variables are not set.
+ * Calculation formula:
+ * KRW = USD × VAT (1.1) × Markup (1.1) × Exchange Rate (1450)
+ * KRW = USD × 1754.5
+ */
+export const KRW_PRICING_DEFAULTS = {
+  /** VAT multiplier (10% VAT) */
+  VAT_MULTIPLIER: 1.1,
+  /** Markup multiplier (10% markup) */
+  MARKUP_MULTIPLIER: 1.1,
+  /** USD to KRW exchange rate */
+  EXCHANGE_RATE: 1450,
+} as const;
+
+/**
+ * KRW pricing configuration interface
+ */
+export interface KRWConfig {
+  exchangeRate: number;
+  vatRate: number;
+  markupRate: number;
+  totalMultiplier: number;
+}
+
+/**
+ * Get KRW pricing configuration from environment variables
+ * Falls back to default values if env vars are not set
+ *
+ * @param env - Cloudflare Worker environment
+ * @returns KRW pricing configuration
+ */
+export function getKRWConfig(env?: { KRW_EXCHANGE_RATE?: string; KRW_VAT_RATE?: string; KRW_MARKUP_RATE?: string }): KRWConfig {
+  const exchangeRate = env?.KRW_EXCHANGE_RATE ? parseFloat(env.KRW_EXCHANGE_RATE) : KRW_PRICING_DEFAULTS.EXCHANGE_RATE;
+  const vatRate = env?.KRW_VAT_RATE ? parseFloat(env.KRW_VAT_RATE) : KRW_PRICING_DEFAULTS.VAT_MULTIPLIER;
+  const markupRate = env?.KRW_MARKUP_RATE ? parseFloat(env.KRW_MARKUP_RATE) : KRW_PRICING_DEFAULTS.MARKUP_MULTIPLIER;
+
+  return {
+    exchangeRate,
+    vatRate,
+    markupRate,
+    totalMultiplier: vatRate * markupRate * exchangeRate,
+  };
+}
+
+/**
+ * Calculate KRW hourly price from USD price
+ * Applies VAT, markup, and exchange rate conversion
+ *
+ * @param usd - Hourly price in USD
+ * @param env - Optional environment for custom rates (uses defaults if not provided)
+ * @returns Price in KRW, rounded to nearest 1 KRW (minimum 1 KRW)
+ *
+ * @example
+ * calculateKRWHourly(0.0075) // Returns 13 (with defaults)
+ * calculateKRWHourly(0.144)  // Returns 253 (with defaults)
+ */
+export function calculateKRWHourly(usd: number, env?: { KRW_EXCHANGE_RATE?: string; KRW_VAT_RATE?: string; KRW_MARKUP_RATE?: string }): number {
+  const config = getKRWConfig(env);
+  const krw = Math.round(usd * config.totalMultiplier);
+  return Math.max(krw, 1);
+}
+
+/**
+ * Calculate KRW monthly price from USD price
+ * Applies VAT, markup, and exchange rate conversion
+ *
+ * @param usd - Monthly price in USD
+ * @param env - Optional environment for custom rates (uses defaults if not provided)
+ * @returns Price in KRW, rounded to nearest 100 KRW (minimum 100 KRW)
+ *
+ * @example
+ * calculateKRWMonthly(5)  // Returns 8800 (with defaults)
+ * calculateKRWMonthly(96) // Returns 168400 (with defaults)
+ */
+export function calculateKRWMonthly(usd: number, env?: { KRW_EXCHANGE_RATE?: string; KRW_VAT_RATE?: string; KRW_MARKUP_RATE?: string }): number {
+  const config = getKRWConfig(env);
+  const krw = Math.round(usd * config.totalMultiplier / 100) * 100;
+  return Math.max(krw, 100);
+}