Tighten import-linter dependency contracts

[peterdsharpe]

Summary

Tighten PhysicsNeMo's import boundaries by making complete contracts exhaustive, assigning previously untracked modules to their intended layers, and making currently independent siblings explicitly non-shareable. The partial nn contract remains non-exhaustive, while compat and conftest remain explicit top-level exceptions.

Before

active_learning : diffusion
sym

samplers : metrics
multi_diffusion : preconditioners : guidance
utils

After

exhaustive = True

deploy | active_learning | diffusion | sym

samplers | metrics
multi_diffusion | preconditioners | guidance
utils | base

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[peterdsharpe]

/ok to test ac3f81b

[github-actions]

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[greptile-apps]

Greptile Summary

Tightens import-linter dependency boundaries while preserving the intentionally non-exhaustive nn contract.

• Makes complete layer contracts exhaustive, with explicit top-level exceptions for compat and conftest.
• Assigns previously untracked modules to their intended layers.
• Marks currently independent modules as non-shareable siblings.

Important Files Changed

Filename	Overview
.importlinter	Exhaustive coverage and sibling boundaries match the current package tree and import graph; no contract-breaking omissions or imports were identified.

_{Reviews (1): Last reviewed commit: "Tighten import-linter contracts" | Re-trigger Greptile}

[peterdsharpe]

/ok to test 2c9b79e

[peterdsharpe]

/ok to test a987505

[coreyjadams]

Thanks, @peterdsharpe , for doing some maintenance here. Good to clean this up periodically. Left a few minor comments but overall its looking good.

[peterdsharpe]

/ok to test 4e7eefb