Batch example

[ddieruf]

What was changed

Added a .NET port of the Java batch samples (samples-java/core/src/main/java/io/temporal/samples/batch), under a new src/Batch directory with one project per pattern:

• Iterator — processes a page of records at a time via child Workflows run in parallel, continuing-as-new between pages.
• HeartbeatingActivity — processes the whole batch inside a single heartbeating Activity, resuming from the last recorded offset after a worker restart instead of starting over.
• SlidingWindow — keeps a fixed number of record-processing child Workflows running in parallel at all times, using completion Signals and continue-as-new to keep history bounded indefinitely; multiple partitions run side by side via BatchWorkflow for higher total throughput.

Each sample follows this repo's existing conventions (dotnet run worker / dotnet run workflow, per-sample README, TemporalioSamples.sln entries) and mirrors the Java sample's file/class structure closely so it's easy to compare side by side.

One deliberate deviation from the Java version: SlidingWindowBatchWorkflow continues-as-new on Workflow.ContinueAsNewSuggested in addition to a fixed page size, rather than relying on the fixed count alone. A fixed count can be outgrown by other accumulated history (e.g. completion Signals) before it's reached — this pattern is based on how we handle the same problem in production. A TestContinueAsNew input flag makes that branch deterministically testable without generating a large amount of real history.

Why?

There was no .NET equivalent of these samples, which came up in a community discussion about batch-processing workarounds (paging through large datasets, bounding history size, safely reporting child-Workflow completion across continue-as-new). This fills that gap using patterns we've validated in a production import pipeline.

Checklist

1. Closes

2. How was this tested:

   • dotnet build / dotnet format --verify-no-changes on the full solution.
   • Added automated tests under tests/Batch/* (xUnit, using WorkflowEnvironment.StartTimeSkippingAsync for the Iterator and SlidingWindow Workflow tests, and ActivityEnvironment for a targeted heartbeat-resume test on HeartbeatingActivity). All pass.
   • Manually ran each sample's worker + starter against a local Temporal dev server end to end and inspected results/history via the temporal CLI. This caught and fixed a real bug during development: SlidingWindowBatchWorkflow's original return value summed to double the actual record count across partitions; it now returns the Signal-tracked progress count instead.

3. Any docs updates needed?

   • Added src/Batch/README.md (overview) plus a README per sample.
   • Added a Batch entry to the root README.md sample index.
   • No docs.temporal.io updates needed.

[CLAassistant]

All committers have signed the CLA.