Force nearest presentation filtering

[mstan]

Summary:

• Forces nearest filtering for presentation textures and supersample targets.
• Overrides SDL render scale quality to point sampling for final presentation.
• Carries forward the useful framebuffer filtering idea from the Zection6V fork without taking unrelated changes.

Validation:

• nds_runner.exe built successfully with compute renderer disabled.

Bead: beads-yjp.39