feat: unify transfer risk rule and fix tight-transfer display

[reidzeibel]

Part of https://github.com/AtB-AS/kundevendt/issues/24416

Background

The same transfer situation was classified by two different rules — one here, one in the app — so planner web and app could disagree about the same trip.

The rule now lives in @atb-as/utils (7.1.0), imported by planner-web (this PR), atb-bff (soon) and mittatb-app (soon).

What changes

• Deletes the local hasTemporalOverlap / hasGuaranteedInterchangeInto and uses getLegTransferRisk from the package instead. The guaranteed-interchange handling from fix: respect guaranteed interchanges when determining trip status #781 is preserved — same maximumWaitTime semantics, just no longer a local copy.
• Transfer risk becomes its own axis. TripPatternStatus narrows to 'valid' | 'stale' (data freshness only) and risk is reported per leg as transferRisk, plus the worst value at trip level.
• Two state instead of one: unlikely below −120 s (error, "Ikke mulig") and the new uncertain at 0…−120 s (info, "Usikker overgang"). The card now shows the same verdict as the details screen. This will be refined further, but for this step, we are just aligning how it is between planner-web and app.

How will it look like

Situation	Before	After
Transfer with time to spare	—	—
Transfer that is exactly flush (0 s)	—	Usikker overgang (info)
Transfer short by 30 s	Ikke mulig (error)	Usikker overgang (info)
Transfer short by 5 min	Ikke mulig (error)	Ikke mulig (error)
Guaranteed interchange, within maximumWaitTime	—	—
Guaranteed interchange, past maximumWaitTime	Ikke mulig (error)	Ikke mulig (error)
Transfer still broken, that leg's refresh failed	Ikke mulig (error)	Ikke mulig (error)
Transfer now fine, that leg's refresh failed	Ikke mulig (error)	Resultatene kan være utdaterte (info)

started and ended outranks stale, so a started trip will not show "Resultatene kan være utdaterte" message.

Tight transfers

The trip details had no transfer-risk UI at all — only the card chip. It now shows "Usikker overgang" on the leg, styled like the app.

Two display fixes came out of testing a real 23-second transfer, which showed as 15:18 → 15:17 with no message at all:

• The wait section required more than 30 seconds, so short transfers were silently skipped. Any wait now shows, matching the app.
• Arrival times round up and departures round down, so a same-minute transfer read as if the connection left before the arrival. The arrival now rounds down in that case — and only then. A genuinely missed connection still rounds up, so it still looks missed.

Rounding

Real times (arrival → departure)	On main	On this branch
15:17:11 → 15:17:34	15:18 → 15:17	15:17 → 15:17
15:17:10 → 15:17:55	15:18 → 15:17	15:17 → 15:17
15:17:10 → 15:18:40	15:18 → 15:18	unchanged
15:17:10 → 15:20:10	15:18 → 15:20	unchanged
15:18:40 → 15:17:30 (missed)	15:19 → 15:17	unchanged

Kort byttetid message

Wait	On main	On this branch
23 s	no message	Kort byttetid
45 s	Kort byttetid	unchanged
3 min	Kort byttetid	unchanged

Screenshots

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Project	Deployment	Actions	Updated
planner-web	Ready	Preview	Sep 4, 2026 8:54pm UTC