Feat/mapcontrol plugin

[BhattaraiSijan]

Description

Adds MapControl, a floating toolbar over the map with four features. Each can be
enabled/disabled per-mission from the Configure page.

The plugin is bus-only: the React component is MMGIS-independent and a thin wrapper
translates its callbacks into mmgisAPI calls. Map operations that didn't exist yet are
added in core (Map_.js) and exposed over the event bus so any future plugin can reuse them.

Geocode search

On each keystroke we hit the Nominatim API with the URL-encoded query — debounced 300ms,
only firing for queries ≥2 chars, limit=5. No API key or backend (public endpoint). On
selecting a result we reorder Nominatim's bbox ([min_lat,max_lat,min_lon,max_lon]) into
Leaflet order ([[S,W],[N,E]]), fly to it via map:fitBounds, and drop a pin via
map:createLayer.

Basemap switching

Styles come from msv.basemap.styles[] in the mission config (configurable per mission);
if none are defined we fall back to provider defaults, which differ by engine (Leaflet →
raster XYZ tiles, deck.gl → vector style JSON). The active style is matched against
msv.basemap.style. On select we call map:setBasemap, which calls the engine's
setBasemapStyle() — deck.gl swaps the vector style in place; Leaflet rebuilds the tile
layer (handling mapbox://, raw {z}/{x}/{y} templates, and an OSM fallback).

Measure

We subscribe to map:click / map:mousemove, collect two points, and draw the line +
endpoints as a vector layer via map:createLayer. Distance is computed with Turf; the
label is positioned by projecting the segment midpoint via map:latLngToContainerPoint.

Zoom

map:zoomIn / map:zoomOut, clamped to the engine's min/max zoom.

Core changes (beyond the plugin)

New map:* handlers in Map_.js, also exposed as documented methods on mmgisAPI:
setBasemap / getBasemap / getBasemapStyles, zoomIn / zoomOut,
latLngToContainerPoint, and the map:click / map:mousemove event streams.

Two supporting changes were required:

• Engine adapters — LeafletAdapter gained runtime basemap tile rendering (it had
  none before); DeckGLAdapter gained setStyle and normalized {lat,lng} pointer-event
  emission.
• Configure page — basemap config now applies to any engine (was deck.gl-only), and
  new missions get a default view.

Dependency on #90 (imapengine-drawing)

Vector overlays (the measure line and the search pin) are drawn via map:createLayer /
map:removeLayer, which are provided by #90. We deliberately do not define our own
overlay channels — an earlier version added map:addOverlay/map:removeOverlay, which
collided by name with #90's (their addOverlay is a different operation: an HTML element
anchored at a point). Using map:createLayer is the operation we actually need and removes
the duplication. Until #90 merges these two features no-op (guarded, no crash); the rest of
the plugin is self-contained.

Known limitation / future work

MapControl is a floating overlay, not a docked panel, so it bypasses the normal panel-mount
path: it self-mounts at bundle load by polling for the map container and rendering into a
position:fixed layer on document.body. This works but should be replaced by a proper
"floating tool" mount path in the Modern layout so overlays don't have to self-mount.

Testing

Manual only:

• Toggle each of the four features from the Configure page; confirm each appears/hides.
• Test on both a Leaflet and a deck.gl mission.
• Basemap switcher: confirm the list populates (it retries until the map registers its
  handlers) and switching restyles the map on both engines.
• Search: type a place, confirm results, select one, confirm fly-to + pin.
• Measure: click two points, confirm line + distance label. (Requires feat(core): drawing primitives + overlay + bus surface on IMapEngine #90 for the overlay.)
• Zoom: confirm in/out and that it stops at min/max.

[slesaad]

can you use the skill i shared to make this component align with the reusable components pattern?

[BhattaraiSijan]

Refractored to monorepo pattern in this

[slesaad]

some of the files in this folder can be shared between tools, see current development branch for pattern