fix: make dashboard prometheus queries work with cloud data sources

[arkbriar]

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What's changed and what's your intention?

1. Update the Prometheus queries used in the meta dashboard service to accommodate the cloud data sources where

• the job label doesn't have the same meaning
• a new label component is provided to express the node roles

2. Add standalone in the filter in order to get data for standalone deployments. However, the meta dashboard (web) itself needs a change to accommodate with the model itself.

The query works as long as job and component are not provided simultaneously and identically.

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

• My PR needs documentation updates.

Release note

[gru-agent]

This pull request has been modified. If you want me to regenerate unit test for any of the files related, please find the file in "Files Changed" tab and add a comment @gru-agent. (The github "Comment on this file" feature is in the upper right corner of each file in "Files Changed" tab.)