energy_price_cap_levels_annex_9: Promoting changes to process new format (Oct-Dec 2026 release)

[eglucas]

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Description

energy_price_cap_levels_annex_9. Changes are outlined in this issue that is now fixed: #85

Type of promotion

• Existing pipeline - code/data update
• New pipeline - first promotion to prod

Instructions for reviewer

N/A

Checklist

Pipeline run

• Manual pipeline run completed successfully on dev after merging to dev (link the run below)
• Dev S3 output spot-checked; row counts and values look reasonable
• No unexpected nulls or schema changes in output parquet files

Image freshness

• dev-latest in ECR was rebuilt from the tip of dev that includes this PR's changes
  (check the "Build and push Docker Image to ECR" run in Actions, as promotion only re-tags
  the existing image, it doesn't rebuild)

Code quality

• run-tests workflow passed on this PR
• No hardcoded credentials or environment-specific values

Breaking changes

• No breaking schema changes, OR downstream impact documented below
• No changes to silver/gold dataset column names or types that would break Superset
  

After merging

• Trigger the "Run pipeline in prod" workflow to actually refresh prod data — merging this
  PR only re-tags the image, it does not run the pipeline. Requires approval from at least one of named CODEOWNERS.

Notes

Successful dev run: https://github.com/nestauk/asf_mission_data/actions/runs/32947269792