Add replay-aware logger to Amazon.Lambda.DurableExecution

[GarrettBeatty]

Stacked PRs:

• ->Add replay-aware logger to Amazon.Lambda.DurableExecution #2371
• Adds retry support to the Amazon.Lambda.DurableExecution #2363
• Add durable execution Step + Wait end-to-end #2360

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What

Implements context.Logger, the replay-aware ILogger described in Docs/durable-execution-design.md and shipped by the Python / Java / JavaScript reference SDKs.

Public API surface introduced:

Type	Purpose
IDurableContext.Logger	Replay-safe ILogger (was NullLogger.Instance).
IDurableContext.ConfigureLogger(LoggerConfig)	Swap the inner logger and/or disable replay-aware filtering.
LoggerConfig	CustomLogger + ModeAware configuration record.

Why

Without replay-aware logging, every Console.WriteLine (or any non-suppressing logger) repeats on every replay invocation. A 30-step workflow re-invoked 30 times produces 30 copies of every log line — noisy at best, misleading at worst. The reference SDKs all solve this by reading replay state on each log call and suppressing emission while the workflow is re-deriving prior operations from checkpoint state. This PR ports that behavior to .NET on top of the per-operation replay tracker introduced in #2360.

How

ReplayAwareLogger. An ILogger decorator that consults ExecutionState.IsReplaying on every call. Short-circuits both Log<TState> and IsEnabled during replay so LoggerExtensions.LogXxx doesn't even format the message string. BeginScope always passes through so the scope stack stays balanced — suppression only applies at log emission.

Default inner logger. LambdaCoreLogger — a minimal in-package adapter that delegates to Amazon.Lambda.Core.LambdaLogger.Log, so logs flow into the standard Lambda runtime pipeline (JSON when AWS_LAMBDA_LOG_FORMAT=JSON, level-filtered by AWS_LAMBDA_LOG_LEVEL). Avoids forcing a dependency on Amazon.Lambda.Logging.AspNetCore. Users who want Serilog/Powertools/etc. swap their own logger via ConfigureLogger.

Metadata scopes. DurableFunction.WrapAsyncCore opens a BeginScope around the workflow body carrying durableExecutionArn + awsRequestId. StepOperation opens a per-step scope (operationId, operationName, attempt) around the user-func invocation only. Structured log providers tag every log line emitted by user code with that metadata automatically.

Key files:

• LoggerConfig.cs — public configuration type
• Internal/ReplayAwareLogger.cs — the decorator
• Internal/LambdaCoreLogger.cs — default inner logger
• DurableContext.cs — replaces NullLogger default; implements ConfigureLogger
• DurableFunction.cs — execution-level scope
• Internal/StepOperation.cs — step-level scope around user func

Testing

Unit tests (10 new in Amazon.Lambda.DurableExecution.Tests):

• ReplayAwareLoggerTests (7) — replay suppression, execution passthrough, ModeAware=false, IsEnabled short-circuit, BeginScope passthrough, mid-workflow REPLAY → NEW transition (mirrors Python's test_logger_replay_then_new_logging).
• DurableContextTests (3) — Logger_Default_IsReplayAwareLogger, ConfigureLogger_WithCustomLogger_ReachesUserLogger, ConfigureLogger_ModeAwareFalse_LogsDuringReplay.

Integration test (ReplayAwareLoggerTest in Amazon.Lambda.DurableExecution.IntegrationTests):

End-to-end proof on real AWS infra. Deploys a step → wait(3s) → step workflow that pairs each context.Logger.LogInformation line with a Console.WriteLine "control" line. After the durable execution completes (across two invocations driven by the wait), queries CloudWatch Logs and asserts:

• Each replay-aware line appears exactly once across both invocations.
• Each control line appears once per invocation that reached it (proving the function genuinely replayed).

This pins the suppression contract end-to-end against the actual durable-execution service.

Out of scope (follow-up PRs)

• MapAsync / ParallelAsync / RunInChildContextAsync / WaitForConditionAsync
• CallbackAsync, InvokeAsync
• DefaultJsonCheckpointSerializer
• Annotations source-generator integration / [DurableExecution] attribute
• DurableTestRunner / Amazon.Lambda.DurableExecution.Testing package
• dotnet new lambda.DurableFunction blueprint