Add map search for elements, trips, and places

[dfalling]

Summary

Adds a search overlay on the map that queries elements, trips, and places in a single request, with type-specific behavior on select:

• Element → fly to it + show the preview card. Location-less elements (no coordinates) open their detail modal directly instead of pinning a card over an unrelated map view.
• Trip → filter the map to that trip's elements only, fit the camera to their extent, show a clearable filter chip.
• Place → recenter at a zoom matched to the place's size (country → 4 … city → 11), via placeSearch(granularity: REGIONS).

UX details

• Search runs on submit (not typeahead).
• Collapsed to a top-left icon; tapping out anywhere dismisses it.
• The query + results persist across dismiss, so reopening shows the last search, editable. The field's × clears for a fresh search.
• Results are grouped into Elements / Trips / Places, each styled distinctly.

Implementation

• New Search GraphQL operation; the existing Elements query gained an optional $tripId so one hook + Apollo cache serves both the viewport and trip-filtered views.
• New components: SearchOverlay, TripFilterChip; pure helper placeZoom (with unit tests).
• MapScreen swaps query variables (bounds ↔ tripId) and the displayed-element source based on the active trip filter.

Verification

• tsc, biome, and jest (5 tests) pass.
• All four flows driven manually on an emulator: submit-only search, element fly-to + preview, location-less → detail modal, trip filter + chip clear, place recenter, plus the dismiss/persist/clear behaviors.