fix: remove macro for Qt ver 6.7.0 or later

[DSCaskey]

This removes the Q_DECLARE_TYPEINFO Macro from the VAbstractCurve class for Qt ver 6.7.0 or later that prevents the apps from building.

Closes issue #1427

[what-the-diff]

PR Summary 🌟

• Revamped Documentation 📝
  The makeover of header documentation in vabstractcurve.h has helped tremendously in enhancing its clarity and establishing consistency! It's now so much more readable and easy to follow. 😃

• Updated Copyright Year 📅
  The epoch year for Seamly, LLC's copyright has been updated from 2023 to 2025! This small, yet important detail aligns perfectly with the current business operation. 💼✅

• Polished Comment Layout 🧹
  The unnecessary comment sections were caught and promptly removed, replacing them with a cleaner and more elegant format. Talk about the beautification of our code! 🎉🎊

• Improved Compatibility Checks 💻
  Although the existing inclusion guard was maintained, compatibility checks for QT version were added. Hooray for a smoother and more robust software experience! Kudos to this meticulous work! 💪🎖️

[csett86]

Looking at the definition of a movable type from https://doc.qt.io/qt-6/qtypeinfo.html I think that VAbstractCurve was never movable. So lets just remove that type decl for all qt versions, then its treated as the default Q_COMPLEX_TYPE

@DSCaskey agree?

[DSCaskey]

So lets just remove that type decl for all qt versions,

@csett86 Agreed.

[csett86]

Thank you @DSCaskey