Add RDAP special notice for domains in XAP

[CydeWeys]

When an RDAP lookup is performed for a domain that is currently in the Expiry Access Period (XAP), return HTTP 404 with a custom status notice: "This domain is currently available for registration in the Expiry Access Period". This behavior mirrors how BSA-blocked domains return specialized RDAP notices.

To optimize performance and eliminate redundant Cloud SQL database calls on 404 queries:

• Expose loadMostRecentByDomainName in DomainCache and MultilayerDomainCache to retrieve soft-deleted domains without filtering them out, while preserving temporal projections.
• Update SyncRemoteCacheAction to retain soft-deleted domains in Valkey for the duration of the XAP window on XAP-enabled TLDs instead of immediately deleting them, allowing RDAP lookups to be served directly from Valkey with 0 database queries.
• Evaluate XAP eligibility entirely in-memory in RdapDomainAction using the already-loaded domain object.
• Add comprehensive unit tests in RdapDomainActionTest, MultilayerDomainCacheTest, SyncRemoteCacheActionTest, and DomainFlowUtilsTest.

TAG=agy
CONV=214408e9-2dbb-44b8-af91-1ca29401d1f5
BUG=http://b/553509095

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This change is 

[gbrodman]

@gbrodman reviewed 16 files and all commit messages, and made 8 comments.
Reviewable status: all files reviewed, 7 unresolved discussions (waiting on CydeWeys).

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core/src/main/java/google/registry/batch/SyncRemoteCacheAction.java line 96 at r1 (raw file):

  @Inject
  @Config("domainExpiryAccessPeriodTotalLength")
  Duration domainExpiryAccessPeriodTotalLength = Duration.ofDays(10);

Inject via constructor, like the rest of the fields. No need for default.

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core/src/main/java/google/registry/batch/SyncRemoteCacheAction.java line 200 at r1 (raw file):

      String key = getKeyFunction.apply(resource);
      if (shouldSaveResourceInRemoteCache(resource, tm().getTxTime())) {
        toSaveBuilder.add(new SimplifiedJedisClient.JedisResource<>(key, resource));

The simplified jedis client, for now, sets the expiration time of the object to the deletion time. We'll probably need to change that, I would think.

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core/src/main/java/google/registry/cache/DomainCache.java line 30 at r1 (raw file):

   * domains.
   */
  default Optional<Domain> loadMostRecentByDomainName(String domainName) {

this is not a good name, especially in relation to the other method

like, if i read this i'm like "what, does the other method not load the most recent?"

And if it's meant for use in CacheModule when Valkey isn't configured, it doesn't work -- that delegates loadByDomainName() to FKUtils.loadResourceByCache which filters out deleted domains

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core/src/main/java/google/registry/cache/MultilayerEppResourceCache.java line 67 at r1 (raw file):

  @SuppressWarnings("unchecked")
  protected Optional<V> loadMostRecentFromCaches(Class<V> clazz, String key) {

so this is just the method above without the deletion filtering? that method should probably just call this one then and do the filtering

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core/src/main/java/google/registry/model/ForeignKeyUtils.java line 413 at r1 (raw file):

   */
  @SuppressWarnings("unchecked")
  public static <E extends EppResource> Optional<E> loadMostRecentResourceByCache(

again i don't like the name here. Emphasize that this includes deleted resources.

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core/src/main/java/google/registry/rdap/RdapDomainAction.java line 50 at r1 (raw file):

public class RdapDomainAction extends RdapActionBase {

  @Inject

inject this in the constructor

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core/src/main/java/google/registry/rdap/RdapObjectClasses.java line 560 at r1 (raw file):

  @RestrictJsonNames({})
  @SuppressWarnings("UnusedVariable")
  public static class DomainInExpiryAccessPeriodErrorResponse extends ReplyPayloadBase {

this could possibly share a common base class with the BSA error exception but it's not a big deal

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core/src/test/java/google/registry/batch/SyncRemoteCacheActionTest.java line 172 at r1 (raw file):

    verifyMetrics(SUCCESS);
  }

will also need to test a proper Valkey expiry for when XAP is enabled