feat(blending): early return when steps <= num stops

[lrstanley]

Changes in this PR

• Blending: added a simple early return for cases when the user provides the same number (or lower #) of steps vs stops.
  • Improves performance in edge cases, and allows for bypassing of blending in downstream components that use blending, when the user wants to fully control the blending generation themselves.
  • Makes the return value slightly more consistent (1 step == 1-length array, whereas we pinned to a minimum of 2-length arrays before).

Misc

• I have read CONTRIBUTING.md.

[aymanbagabas]

Thank you @lrstanley!