feat: warnings when instance resources are linked

Signed-off-by: Rachel Powers <508861+Ryex@users.noreply.github.com>

launcher/minecraft/mod/Resource.h

@@ -94,6 +94,19 @@ class Resource : public QObject {
     // Delete all files of this resource.
     bool destroy();
 
+    [[nodiscard]] auto isSymLink() const -> bool { return m_file_info.isSymLink(); }
+
+    /**
+     * @brief Take a instance path, checks if the file pointed to by the resource is a symlink or under a symlink in that instance
+     * 
+     * @param instPath path to an instance directory
+     * @return true 
+     * @return false 
+     */
+    [[nodiscard]] bool isSymLinkUnder(const QString& instPath) const;
+
+    [[nodiscard]] bool isMoreThanOneHardLink() const;
+
    protected:
     /* The file corresponding to this resource. */
     QFileInfo m_file_info;