How to reproduce:
1. Create a new HDRP project
2. In the Project window, right-click -> Create -> Shader Graph -> Any Shader Graph
3. Open the "Create Node" menu -> Expression
4. Below the "Type" field, delete everything and enter the ";"
Expected results: The compiler rejects this or handles it gracefully
Actual results: The node becomes broken with the error that is not really helpful for the user
Reproducible with: 6000.5.0b9, 6000.6.0a6
Can't test with: 6000.0.76f1, 6000.3.15f1, 6000.4.8f1 (No Expression node)
Reproducible on: macOS Tahoe 26 (M1)
Not reproducible on: No other environment tested
Note: While this might be expected, from the usablity point, this edge case is not handled well