Add initial Go CLI skeleton

internal/db/open.go

@@ -0,0 +1,38 @@
+package db
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"os"
+	"path/filepath"
+
+	_ "modernc.org/sqlite"
+)
+
+func Open(ctx context.Context, dbPath string) (*sql.DB, error) {
+	if err := ensureParentDir(dbPath); err != nil {
+		return nil, err
+	}
+
+	db, err := sql.Open("sqlite", dbPath)
+	if err != nil {
+		return nil, fmt.Errorf("open sqlite database: %w", err)
+	}
+
+	if err := applyPragmas(ctx, db); err != nil {
+		_ = db.Close()
+		return nil, err
+	}
+
+	return db, nil
+}
+
+func ensureParentDir(dbPath string) error {
+	parent := filepath.Dir(dbPath)
+	if parent == "." || parent == "" {
+		return nil
+	}
+
+	return os.MkdirAll(parent, 0o755)
+}