Auto-create wallet on first balance check and show deposit info

- billing-agent: auto-create wallet if not exists, include deposit
  account info when balance is 0
- wallet-tool: auto-create wallet on balance check instead of error

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

src/agents/billing-agent.ts

@@ -122,7 +122,7 @@ export class BillingAgent extends BaseAgent<BillingSession> {
 
     switch (walletArgs.action) {
       case 'balance':
-        return this.handleBalance(userId, db);
+        return this.handleBalance(userId, db, env);
       case 'account':
         return this.handleAccount(env);
       case 'request':
@@ -136,7 +136,7 @@ export class BillingAgent extends BaseAgent<BillingSession> {
     }
   }
 
-  private async handleBalance(userId: string, db: D1Database): Promise<string> {
+  private async handleBalance(userId: string, db: D1Database, env: Env): Promise<string> {
     try {
       const wallet = await db.prepare(
         `SELECT balance, currency, updated_at FROM wallets
@@ -144,24 +144,47 @@ export class BillingAgent extends BaseAgent<BillingSession> {
       ).bind(userId).first();
 
       if (!wallet) {
+        // Auto-create wallet
+        await db.prepare(
+          `INSERT INTO wallets (user_id, balance, currency)
+           VALUES ((SELECT id FROM users WHERE telegram_id = ?), 0, 'KRW')
+           ON CONFLICT (user_id) DO NOTHING`
+        ).bind(userId).run();
+
         return JSON.stringify({
           balance: 0,
           currency: 'KRW',
-          message: '지갑이 아직 생성되지 않았습니다.',
+          message: '지갑이 생성되었습니다. 현재 잔액은 0원입니다.',
+          deposit_account: this.getDepositAccountInfo(env),
         });
       }
 
-      return JSON.stringify({
+      const result: Record<string, unknown> = {
         balance: wallet.balance,
         currency: wallet.currency,
         last_updated: wallet.updated_at,
-      });
+      };
+
+      // 잔액 0이면 입금 계좌 안내도 포함
+      if (wallet.balance === 0) {
+        result.deposit_account = this.getDepositAccountInfo(env);
+      }
+
+      return JSON.stringify(result);
     } catch (error) {
       logger.error('잔액 조회 오류', error as Error, { userId });
       return JSON.stringify({ error: '잔액 정보를 조회할 수 없습니다.' });
     }
   }
 
+  private getDepositAccountInfo(env: Env) {
+    return {
+      bank_name: env.DEPOSIT_BANK_NAME || '(설정 필요)',
+      account_number: env.DEPOSIT_BANK_ACCOUNT || '(설정 필요)',
+      account_holder: env.DEPOSIT_BANK_HOLDER || '(설정 필요)',
+    };
+  }
+
   private handleAccount(env: Env): string {
     const bankName = env.DEPOSIT_BANK_NAME || '(설정 필요)';
     const bankAccount = env.DEPOSIT_BANK_ACCOUNT || '(설정 필요)';

src/tools/wallet-tool.ts

@@ -82,7 +82,15 @@ async function getBalance(db?: D1Database, userId?: string): Promise<string> {
     .first<{ balance: number; currency: string }>();
 
   if (!wallet) {
-    return '예치금 계정이 없습니다. 입금 요청을 하시면 자동으로 생성됩니다.';
+    await db
+      .prepare(
+        `INSERT INTO wallets (user_id, balance, currency)
+         VALUES (?, 0, 'KRW')
+         ON CONFLICT (user_id) DO NOTHING`
+      )
+      .bind(user.id)
+      .run();
+    return '지갑이 생성되었습니다. 현재 잔액: 0원(KRW)';
   }
 
   return `현재 잔액: ${wallet.balance.toLocaleString()}${wallet.currency}`;