PostgreSQL 의존성 및 내부 유틸리티 추가:

- `github.com/lib/pq` PostgreSQL 드라이버 vendor 디렉토리에 추가.
- PostgreSQL 관련 내부 패키지(`pqsql`, `proto`, `pqtime`, `pgpass`, `pgservice`, `pqutil`) 구현:
  - SQL 어휘 처리, 프로토콜 상수 및 구조 정의, 시간 파서/포맷터(`Parse`, `Format`).
  - `.pgpass` 파일 및 `pg_service.conf` 관리 기능 추가.
  - 파일/사용자 권한 검증 및 플랫폼별 사용자 정보 조회 기능 포함.
- 데이터베이스 초기화 로직 추가 (`services/db.go`):
  - PostgreSQL 연결 설정 및 초기 스키마 생성.
- 자동매매 관련 DB 레포지토리(`services/autotrade_repo.go`) 구현:
  - 자동매매 규칙 및 포지션 관리 로직 추가 (`dbInsertRule`, `dbLoadRules` 등).

vendor/github.com/lib/pq/internal/pqutil/perm.go

@@ -0,0 +1,64 @@
+//go:build !windows && !plan9
+
+package pqutil
+
+import (
+	"errors"
+	"os"
+	"syscall"
+)
+
+var (
+	ErrSSLKeyUnknownOwnership    = errors.New("pq: could not get owner information for private key, may not be properly protected")
+	ErrSSLKeyHasWorldPermissions = errors.New("pq: private key has world access; permissions should be u=rw,g=r (0640) if owned by root, or u=rw (0600), or less")
+)
+
+// SSLKeyPermissions checks the permissions on user-supplied SSL key files,
+// which should have very little access. libpq does not check key file
+// permissions on Windows.
+//
+// If the file is owned by the same user the process is running as, the file
+// should only have 0600. If the file is owned by root, and the group matches
+// the group that the process is running in, the permissions cannot be more than
+// 0640. The file should never have world permissions.
+//
+// Returns an error when the permission check fails.
+func SSLKeyPermissions(sslkey string) error {
+	fi, err := os.Stat(sslkey)
+	if err != nil {
+		return err
+	}
+
+	return CheckPermissions(fi)
+}
+
+func CheckPermissions(fi os.FileInfo) error {
+	// The maximum permissions that a private key file owned by a regular user
+	// is allowed to have. This translates to u=rw. Regardless of if we're
+	// running as root or not, 0600 is acceptable, so we return if no bits
+	// beyond the regular user permission mask are set.
+	if fi.Mode().Perm()&^os.FileMode(0o600) == 0 {
+		return nil
+	}
+
+	// We need to pull the Unix file information to get the file's owner.
+	// If we can't access it, there's some sort of operating system level error
+	// and we should fail rather than attempting to use faulty information.
+	sys, ok := fi.Sys().(*syscall.Stat_t)
+	if !ok {
+		return ErrSSLKeyUnknownOwnership
+	}
+
+	// if the file is owned by root, we allow 0640 (u=rw,g=r) to match what
+	// Postgres does.
+	if sys.Uid == 0 {
+		// The maximum permissions that a private key file owned by root is
+		// allowed to have. This translates to u=rw,g=r.
+		if fi.Mode().Perm()&^os.FileMode(0o640) != 0 {
+			return ErrSSLKeyHasWorldPermissions
+		}
+		return nil
+	}
+
+	return ErrSSLKeyHasWorldPermissions
+}