Add resourceId to slash explain requests

What does this merge request do and why?

A few months ago the slash explain graphql endpoint was tweaked so that it no longer accepts requests without a ResourceId (the feature flag is not active in production yet, but it already affects the test in STG).

This MR:

• Updates the slash command handler to pass a ResourceId (we can send it in production as well, even though it's not required there yet)|
• Separate the test case coercing logic for code explanation and slash explain
• Update the daily run config to take a new code explanation dataset (_V5 which has the resource_id column added)

Relates to #479 (closed)

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

Merge request checklist

• I've ran the affected pipeline(s) to validate that nothing is broken.
  • Staging: dev-ai-research-0e2f8974.aherczeg_test.results_slash_stg__independent_llm_judge
  • Production: dev-ai-research-0e2f8974.aherczeg_test.results_slash_pro__independent_llm_judge
• Tests added for new functionality. If not, please raise an issue to follow up.
• Documentation added/updated, if needed.