Fix(bg motion vectors): gate `BackgroundMotionVectorsPlugin` pipelines to `DownlevelFlags(INDEPENDENT_BLEND)`#24067

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kfc35 wants to merge 3 commits intobevyengine:mainfrom

kfc35:23975_fix_background_motion_vectors

Commits on May 2, 2026

fix(bg motion vectors): gate setting write_mask to `DownlevelFlags(INDEPENDENT_BLEND)`
kfc35
committed
fix: disable bg motion vector pipeline if lacking downlevel flag
kfc35
committed
fix: move init of `PreviousViewUniforms` before check
kfc35
committed