Refactor foundational temporal types to java.time (#3036)

* Migrates core classes (Clock, Sleeper, TransactionManager) and extensive domain models from Joda-Time to java.time.
* Restores original public API method names while substituting parameters/return values with `java.time.Instant`.
* Updates JAXB XJC `bindings.xjb` to natively generate `java.time.Instant` and `java.time.LocalDate`, eliminating `toDateTime` wrapper methods.
* Fixes XML serializers (`DateAdapter`) to robustly convert OffsetDateTime timezone strings to UTC.
* Cleans up redundant imports and Checkstyle failures across the codebase.

Remaining Joda-Time surface area to migrate in future tasks:
* Command-line parameters (e.g. `DateTimeParameter`, `DateParameter`, `IntervalParameter`) in `google.registry.tools.params`.
* EPP/RDAP flow testing infrastructure (`EppTestCase`, `RdapActionBaseTestCase`, `FlowTestCase`).
* Beam pipelines and Load Testing modules (`Spec11PipelineTest`, `RdePipelineTest`, `RegistryJpaReadTest`, `EppClient`).
* Utility bridges and converters (`DateTimeUtils.toDateTime/toInstant`, `DateTimeConverter`, `UtcDateTimeAdapter`).
* Remaining UI Console tests and Actions.

common/src/testing/java/google/registry/testing/FakeClock.java

@@ -14,16 +14,13 @@
 
 package google.registry.testing;
 
-import static google.registry.util.DateTimeUtils.START_OF_TIME;
-import static org.joda.time.DateTimeZone.UTC;
-import static org.joda.time.Duration.millis;
+import static google.registry.util.DateTimeUtils.START_INSTANT;
 
 import google.registry.util.Clock;
+import java.time.Duration;
 import java.time.Instant;
 import java.util.concurrent.atomic.AtomicLong;
 import javax.annotation.concurrent.ThreadSafe;
-import org.joda.time.DateTime;
-import org.joda.time.Duration;
 import org.joda.time.ReadableDuration;
 import org.joda.time.ReadableInstant;
 
@@ -39,12 +36,13 @@ public final class FakeClock implements Clock {
 
   private volatile long autoIncrementStepMs;
 
-  /** Creates a FakeClock that starts at START_OF_TIME. */
+  /** Creates a FakeClock that starts at START_INSTANT. */
   public FakeClock() {
-    this(START_OF_TIME);
+    this(START_INSTANT);
   }
 
   /** Creates a FakeClock initialized to a specific time. */
+  @Deprecated
   public FakeClock(ReadableInstant startTime) {
     setTo(startTime);
   }
@@ -54,12 +52,6 @@ public final class FakeClock implements Clock {
     setTo(startTime);
   }
 
-  /** Returns the current time. */
-  @Override
-  public DateTime nowUtc() {
-    return new DateTime(currentTimeMillis.addAndGet(autoIncrementStepMs), UTC);
-  }
-
   @Override
   public Instant now() {
     return Instant.ofEpochMilli(currentTimeMillis.addAndGet(autoIncrementStepMs));
@@ -74,27 +66,44 @@ public final class FakeClock implements Clock {
    * @param autoIncrementStep the new auto increment duration
    * @return this
    */
+  @Deprecated
   public FakeClock setAutoIncrementStep(ReadableDuration autoIncrementStep) {
     this.autoIncrementStepMs = autoIncrementStep.getMillis();
     return this;
   }
 
+  /**
+   * Sets the increment applied to the clock whenever it is queried. The increment is zero by
+   * default: the clock is left unchanged when queried.
+   *
+   * <p>Passing a duration of zero to this method effectively unsets the auto increment mode.
+   *
+   * @param autoIncrementStep the new auto increment duration
+   * @return this
+   */
+  public FakeClock setAutoIncrementStep(Duration autoIncrementStep) {
+    this.autoIncrementStepMs = autoIncrementStep.toMillis();
+    return this;
+  }
+
   /** Advances clock by one millisecond. */
   public void advanceOneMilli() {
-    advanceBy(millis(1));
+    advanceBy(Duration.ofMillis(1));
   }
 
   /** Advances clock by some duration. */
+  @Deprecated
   public void advanceBy(ReadableDuration duration) {
     currentTimeMillis.addAndGet(duration.getMillis());
   }
 
   /** Advances clock by some duration. */
-  public void advanceBy(java.time.Duration duration) {
+  public void advanceBy(Duration duration) {
     currentTimeMillis.addAndGet(duration.toMillis());
   }
 
   /** Sets the time to the specified instant. */
+  @Deprecated
   public void setTo(ReadableInstant time) {
     currentTimeMillis.set(time.getMillis());
   }
@@ -106,7 +115,7 @@ public final class FakeClock implements Clock {
 
   /** Invokes {@link #setAutoIncrementStep} with one millisecond-step. */
   public FakeClock setAutoIncrementByOneMilli() {
-    return setAutoIncrementStep(Duration.millis(1));
+    return setAutoIncrementStep(Duration.ofMillis(1));
   }
 
   /** Disables the auto-increment mode. */

common/src/testing/java/google/registry/testing/FakeSleeper.java

@@ -19,8 +19,8 @@ import static com.google.common.base.Preconditions.checkNotNull;
 
 import google.registry.util.Sleeper;
 import java.io.Serializable;
+import java.time.Duration;
 import javax.annotation.concurrent.ThreadSafe;
-import org.joda.time.ReadableDuration;
 
 /** Sleeper implementation for unit tests that advances {@link FakeClock} rather than sleep. */
 @ThreadSafe
@@ -35,8 +35,8 @@ public final class FakeSleeper implements Sleeper, Serializable {
   }
 
   @Override
-  public void sleep(ReadableDuration duration) throws InterruptedException {
-    checkArgument(duration.getMillis() >= 0);
+  public void sleep(Duration duration) throws InterruptedException {
+    checkArgument(!duration.isNegative(), "Duration must be non-negative");
     if (Thread.interrupted()) {
       throw new InterruptedException();
     }
@@ -44,8 +44,8 @@ public final class FakeSleeper implements Sleeper, Serializable {
   }
 
   @Override
-  public void sleepUninterruptibly(ReadableDuration duration) {
-    checkArgument(duration.getMillis() >= 0);
+  public void sleepUninterruptibly(Duration duration) {
+    checkArgument(!duration.isNegative(), "Duration must be non-negative");
     clock.advanceBy(duration);
   }
 }