fix(java): upgrade Jackson to 2.18.11 to address CVEs (#4500)

## Summary

The Java SDK pinned `jackson-databind` 2.17.1, and `jackson-core` and
the other Jackson modules came in transitively via `arrow-vector` and
`lance-namespace-apache-client` at 2.16.x–2.17.x, all affected by known
CVEs.

This imports `jackson-bom` 2.18.11 in the parent POM, and declares
`jackson-core`, `jackson-annotations`, `jackson-datatype-jsr310`, and
`jackson-jaxrs-json-provider` as direct (BOM-managed) dependencies of
`lancedb-core`. The direct declarations are needed because the parent's
dependency management doesn't apply to a consumer's transitive
resolution; without them, Maven's nearest-wins mediation still hands
downstream apps the older versions from `arrow-vector`.

## Evidence

`mvn dependency:list` in a separate consumer project depending only on
`lancedb-core`:

| Artifact | Before | After |
|---|---|---|
| jackson-core | 2.16.0 | 2.18.11 |
| jackson-annotations | 2.16.0 | 2.18.11 |
| jackson-databind | 2.17.1 | 2.18.11 |
| jackson-datatype-jsr310 | 2.16.0 | 2.18.11 |
| jackson-jaxrs-base / json-provider | 2.17.1 | 2.18.11 |
| jackson-module-jaxb-annotations | 2.17.1 | 2.18.11 |

## Merge Risk

**Door:** Two-way. Dependency versions only, and they stay within
Jackson 2.x.
**Blast Radius:** `java` dependencies. Downstream users of
`lancedb-core` now get Jackson 2.18.11 transitively.

Fixes OSS-2360, OSS-2337

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

java/pom.xml

@@ -29,6 +29,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <arrow.version>15.0.0</arrow.version>
         <lance-core.version>14.0.0-beta.10</lance-core.version>
+        <jackson.version>2.18.11</jackson.version>
         <spotless.skip>false</spotless.skip>
         <spotless.version>2.30.0</spotless.version>
         <spotless.java.googlejavaformat.version>1.7</spotless.java.googlejavaformat.version>
@@ -62,6 +63,15 @@
 
     <dependencyManagement>
         <dependencies>
+            <!-- Pin every Jackson artifact, including ones pulled in transitively
+                 (e.g. jackson-core), to a single patched version. -->
+            <dependency>
+                <groupId>com.fasterxml.jackson</groupId>
+                <artifactId>jackson-bom</artifactId>
+                <version>${jackson.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
             <dependency>
                 <groupId>org.lance</groupId>
                 <artifactId>lance-core</artifactId>