This commit makes the following major changes
1. Add "sample_baked_with_rotation()" to Curve3D, making it usable independently. A similar change was made to Curve2D previously.
2. Refactor the _bake() method on Curve3D, using Parallel Transport Frame instead of Frenet Frame.
3. Refactor the sample_* methods, including:
i. Factor out common binary search code, following the DRY principe
ii. sample_up_vector() interpolated up vector as part of rotation frame(posture) for consistancy and accuracy.
This makes it easier to spot syntax errors when editing the
class reference. The schema is referenced locally so validation
can still work offline.
Each class XML's schema conformance is also checked on GitHub Actions.
