Add integration test for host metadata resolution (#719)

## 🥞 Stacked PR
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[link](https://github.com/databricks/databricks-sdk-java/pull/719/files)
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[**hectorcast-db/stack/port-7-integration-test-metadata**](#719)
[[Files
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-
[hectorcast-db/stack/port-8-remove-unified-flag](#720)
[[Files
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---------
## Summary

Port of Go SDK
[#1546](databricks/databricks-sdk-go#1546).

Adds an integration test verifying that `config.resolve()` populates
`accountId`, `workspaceId`, and `discoveryUrl` from the host's
`/.well-known/databricks-config` endpoint.

**Changes:**
- `HostMetadataIT`: integration test for metadata resolution (requires
`DATABRICKS_HOST` via `ucws` env context)

`NO_CHANGELOG=true`

## Test plan
- [x] All unit tests pass (no production code changes)
- [x] `HostMetadataIT` runs against live workspace

Author: hectorcast-db

databricks-sdk-java/src/test/java/com/databricks/sdk/integration/HostMetadataIT.java

@@ -0,0 +1,42 @@
+package com.databricks.sdk.integration;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import com.databricks.sdk.core.DatabricksConfig;
+import com.databricks.sdk.integration.framework.EnvContext;
+import com.databricks.sdk.integration.framework.EnvOrSkip;
+import com.databricks.sdk.integration.framework.EnvTest;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Integration test for host metadata resolution via /.well-known/databricks-config. Port of Go SDK
+ * #1546.
+ */
+@ExtendWith(EnvTest.class)
+@EnvContext("ucws")
+public class HostMetadataIT {
+  private static final Logger LOG = LoggerFactory.getLogger(HostMetadataIT.class);
+
+  @Test
+  void testResolvePopulatesFieldsFromMetadata(@EnvOrSkip("DATABRICKS_HOST") String host) {
+    DatabricksConfig config =
+        new DatabricksConfig().setHost(host).setExperimentalIsUnifiedHost(true);
+    config.resolve();
+
+    LOG.info(
+        "Resolved metadata for {}: accountId={}, workspaceId={}, discoveryUrl={}",
+        host,
+        config.getAccountId(),
+        config.getWorkspaceId(),
+        config.getDiscoveryUrl());
+
+    // After resolve(), host metadata should have been resolved
+    assertNotNull(config.getDiscoveryUrl(), "Expected discoveryUrl to be populated after resolve");
+    assertFalse(config.getDiscoveryUrl().isEmpty(), "Expected non-empty discoveryUrl");
+    assertNotNull(config.getAccountId(), "Expected accountId to be populated after resolve");
+    assertFalse(config.getAccountId().isEmpty(), "Expected non-empty accountId");
+  }
+}