feat(file source): Add UNIX owner and group to File source namespace

[Hiruma31]

Summary

This change adds the file owner and group in the file source's namespace.

Vector configuration

data_dir: "/tmp/vector_data"

schema:
  log_namespace: true
# Sources - Read from files
sources:
  my_file_source:
    type: file
    include:
      - /tmp/vector/*.log     

# Transforms - Retrieve from namesapce
transforms:
  basic_remap:
    type: remap
    inputs:
      - my_file_source
    source: |
      # Add custom fields
      .environment = "production"
      .application = "my-app"
      .log.file.path = %file.path
      .log.file.owner = %file.owner
      .log.file.group = %file.group

# Sink - Output to console
sinks:
  console_output:
    type: console
    inputs:
      - basic_remap
    encoding:
      codec: json
    target: stdout

{
    "application": "my-app",
    "environment": "production",
    "log": {
        "file": {
            "group": "usergroup",
            "owner": "youruser",
            "path": "/tmp/vector/check.log"
        }
    }
}

How did you test this PR?

Thiss PR wass tested with a local build of vector 0.52.0 (x86_64-unknown-linux-gnu)

Change Type

• Bug fix
• New feature
• Non-functional (chore, refactoring, docs)
• Performance

Is this a breaking change?

• Yes
• No

Does this PR include user facing changes?

• Yes. Please add a changelog fragment based on our guidelines.
• No. A maintainer will apply the no-changelog label to this PR.

References

• Closes: Include file owner and group in Log Namespace #24290

Notes

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[Hiruma31]

I have read the CLA Document and I hereby sign the CLA