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/doc.go

@@ -0,0 +1,137 @@
+/*
+Package pq is a Go PostgreSQL driver for database/sql.
+
+Most clients will use the database/sql package instead of using this package
+directly. For example:
+
+	import (
+		"database/sql"
+
+		_ "github.com/lib/pq"
+	)
+
+	func main() {
+		dsn := "user=pqgo dbname=pqgo sslmode=verify-full"
+		db, err := sql.Open("postgres", dsn)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		age := 21
+		rows, err := db.Query("select name from users where age = $1", age)
+		// …
+	}
+
+You can also connect with an URL:
+
+	dsn := "postgres://pqgo:password@localhost/pqgo?sslmode=verify-full"
+	db, err := sql.Open("postgres", dsn)
+
+# Connection String Parameters
+
+See [NewConfig].
+
+# Queries
+
+database/sql does not dictate any specific format for parameter placeholders,
+and pq uses the PostgreSQL-native ordinal markers ($1, $2, etc.). The same
+placeholder can be used more than once:
+
+	rows, err := db.Query(
+		`select * from users where name = $1 or age between $2 and $2 + 3`,
+		"Duck", 64)
+
+pq does not support [sql.Result.LastInsertId]. Use the RETURNING clause with a
+Query or QueryRow call instead to return the identifier:
+
+	row := db.QueryRow(`insert into users(name, age) values('Scrooge McDuck', 93) returning id`)
+
+	var userid int
+	err := row.Scan(&userid)
+
+# Data Types
+
+Parameters pass through [driver.DefaultParameterConverter] before they are handled
+by this package. When the binary_parameters connection option is enabled, []byte
+values are sent directly to the backend as data in binary format.
+
+This package returns the following types for values from the PostgreSQL backend:
+
+  - integer types smallint, integer, and bigint are returned as int64
+  - floating-point types real and double precision are returned as float64
+  - character types char, varchar, and text are returned as string
+  - temporal types date, time, timetz, timestamp, and timestamptz are
+    returned as time.Time
+  - the boolean type is returned as bool
+  - the bytea type is returned as []byte
+
+All other types are returned directly from the backend as []byte values in text format.
+
+# Errors
+
+pq may return errors of type [*pq.Error] which contain error details:
+
+	pqErr := new(pq.Error)
+	if errors.As(err, &pqErr) {
+	    fmt.Println("pq error:", pqErr.Code.Name())
+	}
+
+# Bulk imports
+
+You can perform bulk imports by preparing a "COPY [..] FROM STDIN" statement in
+a transaction ([sql.Tx]). The returned [sql.Stmt] handle can then be repeatedly
+"executed" to copy data into the target table. After all data has been processed
+you should call Exec() once with no arguments to flush all buffered data. Any
+call to Exec() might return an error which should be handled appropriately, but
+because of the internal buffering an error returned by Exec() might not be
+related to the data passed in the call that failed.
+
+It is not possible to COPY outside of an explicit transaction in pq.
+
+Use nil for NULL, or explicitly add WITH NULL 'SOME STRING' (the default of \N
+doesn't work).
+
+# Notifications
+
+PostgreSQL supports a simple publish/subscribe model using PostgreSQL's [NOTIFY] mechanism.
+
+To start listening for notifications, you first have to open a new connection to
+the database by calling [NewListener]. This connection can not be used for
+anything other than LISTEN / NOTIFY. Calling Listen will open a "notification
+channel"; once a notification channel is open, a notification generated on that
+channel will effect a send on the Listener.Notify channel. A notification
+channel will remain open until Unlisten is called, though connection loss might
+result in some notifications being lost. To solve this problem, Listener sends a
+nil pointer over the Notify channel any time the connection is re-established
+following a connection loss. The application can get information about the state
+of the underlying connection by setting an event callback in the call to
+NewListener.
+
+A single [Listener] can safely be used from concurrent goroutines, which means
+that there is often no need to create more than one Listener in your
+application. However, a Listener is always connected to a single database, so
+you will need to create a new Listener instance for every database you want to
+receive notifications in.
+
+The channel name in both Listen and Unlisten is case sensitive, and can contain
+any characters legal in an [identifier]. Note that the channel name will be
+truncated to 63 bytes by the PostgreSQL server.
+
+# Kerberos Support
+
+If you need support for Kerberos authentication, add the following to your main
+package:
+
+	import "github.com/lib/pq/auth/kerberos"
+
+	func init() {
+		pq.RegisterGSSProvider(func() (pq.Gss, error) { return kerberos.NewGSS() })
+	}
+
+This package is in a separate module so that users who don't need Kerberos don't
+have to add unnecessary dependencies.
+
+[identifier]: http://www.postgresql.org/docs/current/static/sql-syntax-lexical.html#SQL-SYNTAX-IDENTIFIERS
+[NOTIFY]: http://www.postgresql.org/docs/current/static/sql-notify.html
+*/
+package pq