Beta2 polishes the new trips list and squashes the startup crash beta1 introduced.

Fixed:
- Trips list no longer crashes when saved and auto-detected trips overlap

Changed:
- Date chip on each trip row now shows the year (21 APR 26)
- Long durations cascade units (2d 3h, 1w 2d, 1mo 2w)
- Summary card rounds distance and kWh — no more decimals
- Add leg / Merge trip moved next to the legs card on trip detail
- Internal library and toolchain updates
