fix: evaluate property shapes of nested SHACL shapes

[St4NNi]

Description

Shapes reached through sh:node, sh:or, sh:and, sh:not, sh:xone or sh:qualifiedValueShape have no targets of their own, so their property shapes were never evaluated. The nested check then counted as conforming: a required property missing on a nested node passed, and sh:not over such a shape always failed. Incremental validation had the same gap. A change read only by a nested shape's property shape did not recheck the shapes that reference that nested shape, so a delta result could keep a stale verdict.

Changes

• Evaluate a shape's property shapes for the same focus node when the shape is checked as a nested shape. The top-level path is unchanged and still reaches property shapes through their inherited targets.
• Treat changes to a nested shape's property shapes as changes to that nested shape when selecting delta targets and estimating delta work, so parent shapes are rechecked.
• Add full-validation tests for nested property shapes through each logical and qualified constraint, compared with the reference validator.
• Add an incremental test where removing and restoring a nested property value flips the delta verdict in line with full validation.
• Note the fix in the changelog.