优化fscrypt，添加GUI目标

src/gui/gui_utils.cpp

@@ -0,0 +1,48 @@
+#include "gui_utils.h"
+#include "gui_common.h"
+#include "config.h"
+#include "utils/strings.h"
+#include <windows.h>
+#include <commdlg.h>
+#include <shlobj.h>
+#include <format>
+
+void load_config_file(const std::wstring &path) {
+    g_config_path_w = path;
+    g_config_path = utils::wstr_to_str(path);
+    std::string err;
+    if (parse_config(path, g_cfg, &err)) {
+        g_log_lines.push_back(std::format("[INFO] Config loaded: {}", g_config_path));
+    } else {
+        g_log_lines.push_back(std::format("[ERROR] {}", err));
+    }
+}
+
+std::string open_file_dialog(const char *filter_desc, const char *filter_ext) {
+    wchar_t buf[MAX_PATH] = {};
+    OPENFILENAMEW ofn = {};
+    ofn.lStructSize = sizeof(ofn);
+    ofn.lpstrFile = buf;
+    ofn.nMaxFile = MAX_PATH;
+    ofn.Flags = OFN_FILEMUSTEXIST | OFN_PATHMUSTEXIST;
+
+    std::wstring wfilter = utils::to_wstring(std::string(filter_desc) + '\0' + filter_ext + '\0');
+    ofn.lpstrFilter = wfilter.c_str();
+
+    if (GetOpenFileNameW(&ofn))
+        return utils::wstr_to_str(buf);
+    return {};
+}
+
+std::string open_folder_dialog() {
+    BROWSEINFOW bi = {};
+    bi.hwndOwner = nullptr;
+    bi.ulFlags = BIF_RETURNONLYFSDIRS | BIF_NEWDIALOGSTYLE;
+    LPITEMIDLIST pidl = SHBrowseForFolderW(&bi);
+    if (!pidl) return {};
+
+    wchar_t buf[MAX_PATH] = {};
+    if (!SHGetPathFromIDListW(pidl, buf)) return {};
+    CoTaskMemFree(pidl);
+    return utils::wstr_to_str(buf);
+}