feat(lambda): support for application signals layers

[nikovirtala]

Issue # (if applicable)

Closes #36190

Reason for this change

I wanted to provide the aws-cdk-lib Lambda Function constructs users an easy way to start using Amazon CloudWatch Application Signals.

Description of changes

I added new regional facts for the layer ARNs and the methods to find the correct layer for the specified Runtime, with necessary compatibility checks.

Describe any new or updated permissions being added

The usage requires attaching a policy to the Lambda execution IAM Role. I left it intentionally as a manual step, but I want to discuss with the maintainer whether it could be abstracted away. I thought it will be easier around the code?

Description of how you validated changes

Unit and integration tests are covering the implementation.

Checklist

• My code adheres to the CONTRIBUTING GUIDE and DESIGN GUIDELINES

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license

[aws-cdk-automation]

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[nikovirtala]

Now that I'm looking at the implementation, it could've also been simply a boolean applicationSignalsEnabled: true | false. I suppose it still may be, if you think it is better than this approach, which reuses the existing adotInstrumentation structure.

[nikovirtala]

I would like the API to clearly distinguish the wrapper used by Application Signals, but jsii disagrees:

aws-cdk-lib: aws-lambda/lib/adot-layers.ts:306:3 - error JSII1004: Value '/opt/otel-instrument' is used for multiple enum values: INSTRUMENT_HANDLER, APPLICATION_SIGNALS

Error: aws-cdk-lib: aws-lambda/lib/function.ts:1528:9 - error TS2367: This comparison appears to be unintentional because the types 'AdotLambdaExecWrapper.REGULAR_HANDLER | AdotLambdaExecWrapper.PROXY_HANDLER | AdotLambdaExecWrapper.STREAM_HANDLER | AdotLambdaExecWrapper.SQS_HANDLER' and 'AdotLambdaExecWrapper.INSTRUMENT_HANDLER' have no overlap.

What's the idiomatic way in aws-cdk-lib to deal with issues like this?