feat (pipelines): Follow up on Recent V2 Pipeline Type Implementation

### Describe the feature

I would like to follow up on https://github.com/aws/aws-cdk/issues/33995 which was recently implemented as part of PR https://github.com/aws/aws-cdk/pull/34005

The upgrade in place for the v2 pipeline type in cdk.pipelines is working great. However, when I try to implement the features in V2 pipeline, I see that some properties are not found, for example, `executionMode` and `triggers` are not valid property on `pipelines.CodePipeline` and so I cannot implement the features available in CodePipeline V2:

```typescript
const deploymentPipeline = new pipelines.CodePipeline(this, 'Pipeline', {
pipelineType: codepipeline.PipelineType.V2,
executionMode: codepipeline.ExecutionMode.PARALLEL,
triggers: [{
providerType: codepipeline.ProviderType.GIT,
gitConfiguration: {
push: {
tags: {
includes: ['release-*']
}
}
}
}],
selfMutation: selfMutation,
```
The features I am trying to test are found below. In addition to `executionMode` and `triggers`, I am not sure what else is needed, but I assume the solution would be to implement the same properties in `aws-cdk-lib/aws-codepipeline` to now be in the newly updated construct in `aws-cdk-lib/pipelines`

### Use Case

So that we can take advantage of all the CodePipeline v2 features shown above in the newly updated cdk.pipelines CodePipeline construct

### Proposed Solution

I believe the solution would be to implement the same properties in `aws-cdk-lib/aws-codepipeline` to now be in the newly updated construct in `aws-cdk-lib/pipelines`

### Other Information

The documentation I am looking at is below, and so I would like to ensure these features are available for use on the new construct:

Reference: https://docs.aws.amazon.com/codepipeline/latest/userguide/pipeline-types-planning.html

### Acknowledgements

- [ ] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### CDK version used

2.189.0

### Environment details (OS name and version, etc.)

MacOS Sequoia 15.4.1

Start by comparing the V2 properties available in aws-cdk-lib/aws-codepipeline with the public pipelines.CodePipeline construct, using issue #33995 and PR #34005 for the recent implementation context. Check how pipelineType is exposed and determine the remaining V2 options, including executionMode and triggers. Done means these CodePipeline V2 features can be configured through pipelines.CodePipeline and are covered by the relevant tests.

Written by the indexing model from the issue text.