Querydsl filtering silently ignores nested property paths since GH-2572

[lovrovrlec]

spring-data-rest 5.0.6 (and the sibling GH-2572 backports on the other maintenance lines) drops every
nested query parameter, e.g. ?job.id=1, ?address.city=Paris.

The predicate ends up empty and the endpoint silently returns all rows instead of the filtered set.
Nested paths worked in 5.0.5 and are still fully supported by
QuerydslPredicateBuilder (bindings.getPropertyPath resolves dotted paths).

Cause:
QuerydslAwareRootResourceInformationHandlerMethodArgumentResolver#filterByJacksonVisibility
looks up the entire request-parameter key in MappedJacksonProperties#fieldNameToProperty, which is
keyed by TOP-LEVEL Jackson field names only:

PersistentProperty<?> property = properties.getPersistentProperty(entry.getKey()); // "job.id"
if (property != null) { filtered.put(property.getName(), entry.getValue()); }

"job.id" is never a key, so the parameter is discarded regardless of visibility.
This affects associations that are fully exposed:

in our case the property has no @JsonIgnore and no @RestResource(exported = false),
and getPersistentProperty("job") resolves fine, while getPersistentProperty("job.id") returns null.

The two tests added in 3dc76b8 cover single-segment keys only (@JsonIgnore and @JsonProperty renames),
which is presumably why the regression went unnoticed.

Impact: silent — no 400, no warning. A multi-tenant reporting endpoint filtered by ?job.id=
returns the tenant's entire history instead of one job's rows.

Suggested fix — resolve the key segment by segment, rejecting it if ANY segment is hidden.
This keeps the GH-2572 guarantee (and extends it to nested levels) while restoring nested paths:

private @Nullable String resolvePath(Class<?> type, String key) {
    StringBuilder resolved = new StringBuilder();
    Class<?> currentType = type;
    for (String segment : DOT.split(key)) {
        MappedJacksonProperties properties = jacksonPropertiesLookup.apply(currentType);
        if (properties == null) return null;
        PersistentProperty<?> property = properties.getPersistentProperty(segment);
        if (property == null) return null;              // hidden at this level -> reject whole key
        if (!resolved.isEmpty()) resolved.append(".");
        resolved.append(property.getName());            // honours @JsonProperty renames per segment
        currentType = property.getActualType();
    }
    return resolved.toString();
}

The resolver already holds jacksonPropertiesLookup as Function<Class<?>, MappedJacksonProperties>, so
no new wiring is needed. Happy to submit a PR with a nested-path test alongside the existing ones.