Diagnose and fix 3D physics collisions

Important

• Use the unity cli (unity command --format json) and the unity-cli and unity-pipeline skills for each step.
• Don't use using directives or unqualified types in the snippet for eval, because the compiler only reads using UnityEngine, and a bare AssetDatabase or Object causes errors (CS0246 / CS0103 / CS0104). return what you want to read; it arrives at data.result.result.
• Create a restore point you can roll back to if your changes fail.
• Do only what's asked. Don't change unrelated assets or files.
• Avoid long explanations.
• Never leave verification code in the user's script. Never build logging or detection they didn't ask for, because it clutters their project and console. Read state through eval instead, as described in Final step.

Full topic map

Before you go forward with a workflow or diagnosis:

1. Open and read the documentation page(s) that cover the specific subject related to what you intend to do or fix and check if you've missed anything.
2. Name the file(s) you read in your response.

This is because your training knowledge about Unity might be out of date, incorrect, or for the wrong Unity version.