fix: correct airport last visit date and add next visit

[jonlarson13]

Summary

• The airport stats card picked the flight with the max date across all related flights, so a future booked flight (e.g. a trip next month) could be shown as the "last visit" instead of the actual most recent past visit.
• last visit now only considers flights whose actual arrival/departure time at that airport has already passed.
• Added a next visit label that surfaces the nearest upcoming flight to that airport, when one exists.

Test plan

• Review an airport with both upcoming and past flights — both "last visit" and "next visit" labels should be displayed.
• Review an airport with only an upcoming flight — only the "next visit" label should be displayed.
• Review an airport with only past flights (no upcoming) — only the "last visit" label should be displayed.

Note

Fix airport last visit date and add next visit label in AirportStatsCard

• Replaces the single last-visit derivation in AirportStatsCard.svelte with a getVisitSummary util that scans flights for arrivals/departures, resolves times from actual or scheduled data with timezone awareness, and returns both lastVisitLabel and nextVisitLabel.
• The card now conditionally renders both labels when available, or just one inline with metrics when only one is present.
• Timer logic is lifted out of AirportTimeCard.svelte into AirportDetailsBody.svelte, which now owns a 30-second ticking now and passes it down to both child components.
• Behavioral Change: AirportStatsCard and AirportTimeCard now require a now: Date prop from their parent instead of managing time internally.

^{Macroscope summarized 5ffc36a.}

[jonlarson13]

Feature discussion in #639

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[macroscopeapp]

🟡 Medium airport-details/AirportStatsCard.svelte:48

When an arrival-side visit has no arrival or arrivalScheduled, getVisitSummary falls back to getFlightDateRange(flight.raw.date, …) and localizes it using the destination timezone. flight.raw.date is the flight's departure date, not its arrival date, so for a red-eye or cross-timezone flight the computed visit is localized to the wrong calendar day. This produces an incorrect last visit or next visit label whenever the arrival falls on a different date than the departure in the destination timezone. Consider using an arrival-derived date (or excluding arrival-side visits that lack arrival timing) so the fallback does not localize the departure date against the destination timezone.

🤖 Copy this AI Prompt to have your agent fix this:

In file @src/lib/components/airport-details/AirportStatsCard.svelte around line 48:

When an arrival-side visit has no `arrival` or `arrivalScheduled`, `getVisitSummary` falls back to `getFlightDateRange(flight.raw.date, …)` and localizes it using the destination timezone. `flight.raw.date` is the flight's departure date, not its arrival date, so for a red-eye or cross-timezone flight the computed visit is localized to the wrong calendar day. This produces an incorrect `last visit` or `next visit` label whenever the arrival falls on a different date than the departure in the destination timezone. Consider using an arrival-derived date (or excluding arrival-side visits that lack arrival timing) so the fallback does not localize the departure date against the destination timezone.