Update doc for Collision Handling

[zhx06]

Summary

Update doc for Collision Handling

Detailed description

• Remove TODO
• Add implementation details for overlap checking
• Add guidance for debugging placement collisions

[greptile-apps]

Greptile Summary

This documentation update removes the collision-handling TODO and explains overlap checking and collision-debugging workflows.

• Documents the solver and validator stages for bounding-box and mesh collision checks.
• Clarifies checked object pairs, On exemptions, and passive-obstacle behavior.
• Adds reproducibility, verbosity, Rerun visualization, and fallback-debugging guidance.

Confidence Score: 5/5

The documentation-only PR appears safe to merge.

The documented APIs, overlap pair selection, collision representations, fallback behavior, verbosity controls, and headless Rerun recording align with the implementation, with no actionable inaccuracies identified.

Important Files Changed

Filename	Overview
docs/pages/concepts/object_placement/collision_handling.rst	Adds implementation and debugging guidance that is consistent with the current collision solver, validation, visualization, and pooled-placement behavior.

_{Reviews (1): Last reviewed commit: "address comments" | Re-trigger Greptile}