Shader Graphs are re-imported every time the project is opened when Dynamic Branching for Fog is enabled

Reproduction steps:
1. Open the attached “IN-130562” project
2. Close and re-open the project
3. Observe the Import Activity window (Window > Analysis > Import Activity)

Actual result: All “.shadergraph” files are re-imported
Expected result: All “.shadergraph” files are cached and not re-imported

Reproducible with: 6000.3.8f1, 6000.4.0b8, 6000.5.0a4, 6000.5.0a6
Not reproducible with: 2022.3.71f1, 6000.0.68f1, 6000.5.0a3

Reproducible on: macOS 26.2
Not reproducible on: No other environments tested