feat: add ftp root path setting

internal/application/capture_ftp_test.go

@@ -52,23 +52,52 @@ func TestCaptureAndFTPServiceUploadsAndCopiesFTPPath(t *testing.T) {
 	}
 }
 
-func TestCaptureAndFTPServiceCopiesSFTPHomePath(t *testing.T) {
+func TestCaptureAndFTPServiceCopiesConfiguredRootPath(t *testing.T) {
 	uploader := &fakeFTPUploader{}
 	clip := &fakeClipboard{}
 	svc := &CaptureAndFTPService{
 		Uploader:  uploader,
 		Clipboard: clip,
 		Cfg: domain.FTPConfig{
-			Protocol:   domain.FTPProtocolSFTP,
-			PathPrefix: "images",
+			Protocol:      domain.FTPProtocolSFTP,
+			RootDirectory: "~/ftp/",
+			PathPrefix:    "images",
 		},
 	}
 
 	if err := svc.ExecuteWithBytes(context.Background(), []byte("png")); err != nil {
 		t.Fatalf("upload SFTP screenshot: %v", err)
 	}
-	if clip.text != "~/"+uploader.path {
-		t.Fatalf("expected SFTP home path copied, got %q", clip.text)
+	if clip.text != "~/ftp/"+uploader.path {
+		t.Fatalf("expected configured SFTP root path copied, got %q", clip.text)
+	}
+}
+
+func TestFTPShareTextJoinsConfiguredRootAndRemoteDirectory(t *testing.T) {
+	const relPath = "snapgo/2026/07/20260713-110413-18lnbx.png"
+	const want = "~/ftp/snapgo/2026/07/20260713-110413-18lnbx.png"
+	if got := ftpShareText(domain.FTPProtocolSFTP, "~/ftp/", relPath); got != want {
+		t.Fatalf("ftpShareText() = %q, want %q", got, want)
+	}
+}
+
+func TestFTPShareTextUsesProtocolDefaultWhenRootDirectoryIsEmpty(t *testing.T) {
+	const relPath = "snapgo/2026/07/image.png"
+	tests := []struct {
+		name     string
+		protocol string
+		want     string
+	}{
+		{name: "FTP", protocol: domain.FTPProtocolFTP, want: "/" + relPath},
+		{name: "SFTP", protocol: domain.FTPProtocolSFTP, want: "~/" + relPath},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if got := ftpShareText(tt.protocol, "", relPath); got != tt.want {
+				t.Fatalf("ftpShareText() = %q, want %q", got, tt.want)
+			}
+		})
 	}
 }