fs: add zip mount support. hash: fix not checking open result for file. fs: fix stdio not checking nullptr access.

sphaira/include/yati/source/file.hpp

@@ -10,6 +10,7 @@ namespace sphaira::yati::source {
 struct File final : Base {
     File(fs::Fs* fs, const fs::FsPath& path);
     Result Read(void* buf, s64 off, s64 size, u64* bytes_read) override;
+    Result GetSize(s64* out);
 
 private:
     fs::Fs* m_fs{};