Provide support for more sophisticated path-based constraint description resolution

[wilkinsona]

#42 added support for resolving constraint descriptions for a property on a class. This works well for simple payloads. For more complex payloads it would be useful to be able to resolve constraint descriptions for a nested path. Ideally, the path used to document a field could be reused.

[JunggiKim]

Thanks for keeping this issue open.

I wanted to add a modern use case that still seems relevant:

• nested object paths like a.b.c
• collection element paths like items[].name
• traversal controlled by @Valid / @get:Valid

In practice, teams often keep field paths in REST Docs snippets and want to reuse the same path to resolve Bean Validation constraints, especially for nested request payloads.

This appears closely related to current open constraint topics (#717 and #887), and still consistent with the constraints reference note that currently only property constraints are supported:
https://docs.spring.io/spring-restdocs/reference/documenting-your-api/constraints.html

If helpful, I can also prepare a PR proposal aligned with your preferred explicit API direction.

Thank you for your time.

[JunggiKim]

Small concrete example for context:

record Request(
    @Valid Filter filter,
    @Valid List<Item> items
) {}
record Filter(@NotBlank String searchType) {}
record Item(@NotBlank String name) {}

When documenting fields such as:

• filter.searchType
• items[].name

it would be very helpful if constraint descriptions could be resolved using the same nested field path.

Thank you again for considering this.