Expand Trips summary with energy, efficiency, and cost metrics

[raykellyjr]

Summary

• expand the Trips summary card with energy used, average efficiency, energy charged, charging cost, and cost per 100 distance units
• calculate filtered-range totals in a small pure TripsSummaryCalculator
• keep known charging costs visible while clearly labeling partial cost coverage
• use the configured currency and existing metric/imperial unit labels
• localize the partial-cost note in all supported languages

This is fully read-only. It uses trip data already loaded by the app and adds no vehicle commands, polling, API calls, or persistence changes.

Verification

• ./gradlew :app:testDebugUnitTest
• ./gradlew :app:lintDebug
• ./gradlew :app:assembleDebug

All pass locally.

[raykellyjr]

Polished this branch for cost honesty:

• Cost / 100 km|mi now only appears when every charge in the filtered trips is priced
• Known charge totals still show under partial coverage, with the existing coverage note
• Added a note when trips include charges but none are priced
• Locked this down with unit tests (including zero-cost = priced/complete)
• Changelog entry added under Unreleased

:app:testDebugUnitTest (TripsSummaryCalculatorTest) and :app:lintDebug pass.

[raykellyjr]

Superseded by the broader analytics leap in #334 (includes this trips-summary work plus trip highlights, cost analytics/widget, and battery history). Happy to close this PR in favor of #334 once you prefer that path.

[raykellyjr]

This PR’s trips-summary work is included (and extended) in #334. Prefer reviewing/merging #334; this one can be closed afterward to avoid duplicate surface area.

[raykellyjr]

Closing in favor of the broader #334 which includes this trips summary work plus trip highlights, cost analytics/widget, and battery history.