bug fix: Clicking on a sample should highlight it when there are query filters and sum by values

[yomete]

When profiling data is filtered with both matchers and sumBy value(s), selecting a profile in the metrics graph fails to highlight the point.

Steps to reproduce:

1. Go to demo.parca.dev/devel
2. Filter profiles (e.g., container="parca-agent")
3. Add a sumBy value (e.g., "comm")
4. Attempt to select a profile in the metrics graph

This is happening because the findSelectedProfile function uses label matchers from the query expression to determine
the selected series. With sumBy, series are limited to the sumBy value, causing the function to fail as it looks for non-existent label sets.

The fix here ensures that we are correctly identifying the selected series based on the profile matchers alone or a combination of the profile matchers and the sumBy value (and prioritizing the sumBy label names and values if present).

[alwaysmeticulous]

🤖 Meticulous spotted visual differences in 4 of 589 screens tested: view and approve differences detected.

_{Last updated for commit d803854. This comment will update as new commits are pushed.}

[brancz]

nice find!