Redistribute SMB transforms with side inputs

[yolgun]

Summary

• redistribute SMB bucket offsets with Reshuffle.viaRandomKey when TransformWithSides is used
• keep TransformWithNoSides topology unchanged
• add pipeline topology assertions for both paths

This prevents runner forward chaining from pinning side-input SMB work to workers available when processing starts, allowing workers that join later to receive work.

Tests

• scio-smb/test: 173 passed, 0 failed
• scio-smb/Compile/javafmtCheck: passed
• scio-smb/Test/javafmtCheck: passed
• git diff --check: passed
• repository-wide sbt test: SMB and other applicable suites passed, but the aggregate command exited non-zero for unrelated local-environment failures:
  • Annoy tests load an x86_64 native library on this arm64 machine
  • scio-snowflake/update expects a missing local Maven artifact at org/bouncycastle/bcprov-jdk15on/1.70

The PR remains in draft pending CI and Flink validation.