Rewrite Save Data & Impl Save Data Dialog (#824)

* core: Rewrite PSF parser & add encoder

add .sfo hex pattern to /scripts

* core/fs: allow to mount path as read-only

* common: Add CString wrapper to handle native null-terminated strings

* SaveData: rewrite to implement full functionality

* mock value for SYSTEM_VER

* SavaData: backup features

* SavaData: SaveDataMemory features

* imgui Ref-counted textures

- has a background thread to decode textures

* imgui: rework gamepad navigation

* PSF: fixed psf not using enum class for PSFEntryFmt (was a standard old ugly enum)

- Add null check to CString when itself is used in a nullable field

* SaveDataDialog implementation

- Fix Mounting/Unmounting check of SaveInstance

src/common/string_util.cpp

@@ -14,12 +14,17 @@
 
 namespace Common {
 
-std::string ToLower(std::string str) {
-    std::transform(str.begin(), str.end(), str.begin(),
-                   [](unsigned char c) { return static_cast<char>(std::tolower(c)); });
+std::string ToLower(std::string_view input) {
+    std::string str;
+    str.resize(input.size());
+    std::ranges::transform(input, str.begin(), tolower);
     return str;
 }
 
+void ToLowerInPlace(std::string& str) {
+    std::ranges::transform(str, str.begin(), tolower);
+}
+
 std::vector<std::string> SplitString(const std::string& str, char delimiter) {
     std::istringstream iss(str);
     std::vector<std::string> output(1);