Unable to see the Unpack solution (powerapp) file in Azure repo,We have run the pipeline

1, Your understanding of the pipeline running process is wrong.

Since you design a pipeline with job run on an agent, so pipeline will run the pipeline based on the agent.

By default, DevOps pipeline will run based on Microsoft hosted agent.

In this situation, pipeline will request a random VM machine which match the agent type and version design(Every time you run the pipeline, the VM will be different.).

Or you can set up a self hosted agent and run your pipeline based on it.

In this situation, pipeline will always run based on the machine that the agent set up on.

2, Why you can't see anything changed on your repository?

That is because the pipeline will not do operations directly on the repository that the pipeline based on.

Before you start those steps:

Pipeline has an default additional step, that step is check-out.

For check-out, you can simply understand it as a copy. By default, the pipeline will "copy" the repo that the pipeline is currently based on to the workspace (relevant folder) of the machine where the pipeline is located. All operations you do are based on this copy, and the repository itself will not be affected in any way.

If you want to see the contains of this folder:

You can add a new task to show the contents. The below is a sample.

For example, SolutionName on my side is 'soluName':

Create files in directory 'soluName':

Show contents in directory 'soluName' of '$(Build.SourcesDirectory':

(By the way, $(Build.SourcesDirectory on your side seems lack a dot.)

3, If you indeed need push back to original repository, there is a method. just follow the below steps.

Step1, allow script to access OAuth token

Step2, give contribute permission to build service account.

Step3, use these commands to push back changes:

git config --global user.email "xxx@xxx.com"
git config --global user.name "<Your Name Here>"

git add .

git commit -m 1

git show-ref

git push origin HEAD:main

After all, I can successfully push back the changes to the repository:

Let me know whether all of the above can answer your question.