fix: separate consumption by fuel type

[gwenvador]

Summary

• separate full-to-full consumption calculations by effective fuel type
• keep primary-fuel averages independent from secondary fuels and auxiliary fluids such as AdBlue
• treat legacy NULL fuel-type rows as the vehicle primary fuel
• add AdBlue to the available fuel types
• show the effective fuel type in the Fuel Logs table
• render separate labelled consumption-trend series for Diesel, AdBlue, and other fuel types

Why

A secondary AdBlue refill could become the previous full-tank anchor, be included in diesel volume, and appear in the same Fuel Consumption Trend series. This produced incorrect diesel L/100 km values.

Fixes #319.
Related to #221.

Testing

• Added regression coverage ensuring a full AdBlue entry does not affect diesel full-to-full consumption.
• Added coverage for independent primary and secondary-fluid averages.
• Added coverage for legacy NULL fuel-type rows inheriting the primary vehicle fuel.
• python -m pytest tests/test_fuel.py tests/test_api.py -q — 90 tests passed in the project Docker environment.

[coderabbitai]

Important

Draft PR not reviewed

Draft PRs are not automatically reviewed by default.

• Trigger a manual review

To automatically review draft PRs, update your CodeRabbit configuration:

reviews:
  auto_review:
    drafts: true

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}