Add self-contained ai.chalk:chalk-java-shaded artifact (version-independent)

[karthikk-01]

Summary

Adds a second published coordinate, ai.chalk:chalk-java-shaded — the same client + Flink connector as chalk-java, but with every third-party dependency relocated into ai.chalk.shaded.*. It's self-contained, so it works on any classpath regardless of what protobuf/grpc/jackson/arrow/netty versions a consumer (or their Flink/Spark runtime) pins.

Why

A consumer pinned below our dependency versions hits linkage errors — e.g. a client on protobuf 3.19 gets:

java.lang.NoClassDefFoundError: com/google/protobuf/MapFieldReflectionAccessor
    at ai.chalk.protos.chalk.server.v1.AuthServiceGrpc.getGetTokenMethod(...)

MapFieldReflectionAccessor is a protobuf 3.25 class our generated stubs need, but the older protobuf on their classpath wins. We can't ask every consumer to change their pinned versions, and we can't shade protobuf into the main chalk-java (its query API exposes ai.chalk.protos.* types). So this ships a separate, fully-relocated artifact for exactly these conflict-prone environments (Flink connector use is the driver — its public API exposes zero third-party types).

What changed

• com.gradleup.shadow plugin + a shadowJar that relocates com.google (protobuf/guava/gson/flatbuffers/api-protos), io.grpc, io.netty, io.perfmark, com.fasterxml.jackson, org.apache.arrow, org.apache.commons, org.yaml.snakeyaml → ai.chalk.shaded.*, with mergeServiceFiles() so gRPC's ServiceLoader providers are rewritten too.
• A chalk-java-shaded MavenPublication with a dependency-free POM (built manually, not from components.java) — critical: if the POM declared the deps, consumers would pull protobuf 3.25 transitively and re-hit the conflict.
• Not relocated (intentional): org.slf4j (excluded — logging facade binds to the runtime), javax.annotation, com.github.luben (zstd-jni — native JNI, relocation breaks the .so symbol binding), org.apache.flink (compileOnly, provided by the cluster).

Verification (local)

Ran the exact failing call from the crash with protobuf 3.19.0 on the classpath:

Classpath	Result
shaded jar + protobuf 3.19	✅ PASS — getGetTokenMethod() returns ai.chalk.shaded.grpc.MethodDescriptor
unshaded chalk-java + protobuf 3.19	❌ reproduces the MapFieldReflectionAccessor crash (proves the test is real)

Also verified: com/google/protobuf fully relocated (0 unshaded), ai.chalk.protos/ai.chalk.flink untouched, gRPC ServiceLoader files rewritten to shaded provider names, and the generated chalk-java-shaded POM is dependency-free with clean metadata.

Consume

implementation("ai.chalk:chalk-java-shaded:<version>")   // instead of chalk-java, for pinned-version envs

Needs a maintainer eye before release

I could verify the artifact + POM locally (shadowJar, generatePomFile, publishToMavenLocal), but not the actual Central Portal upload of this second coordinate — that runs in CI with signing secrets. Please confirm on first release that publishAllPublicationsToMavenCentral picks up the shaded publication (vanniktech is single-artifact-oriented; the manual publication is signed by signAllPublications() and should be bundled, but it's worth watching the first publish).