refactor(street-level): rename the Mapillary layer to street-level

Pure move: the layer id, panel id, CSS prefix, classes, exports and config
paths become provider-neutral (street-level, #street-level-panel, sl-);
the Mapillary-specific modules move under providers/mapillary/. Behaviour
is unchanged. The two sprite collections now register under distinct ids
instead of overwriting each other under 'mapillary'.

Co-Authored-By: Claude Fable 5.1 <[email protected]>

src/app/constructCatalog.js

@@ -25,7 +25,7 @@ import { createApplicationFirms } from './layers/firms.js';
 import { createApplicationEarthquakes } from './layers/earthquakes.js';
 import { createApplicationFirePerimeters } from './layers/perimeters.js';
 import { createApplicationCables } from './layers/submarineCables.js';
-import { createApplicationMapillary } from './layers/mapillary.js';
+import { createApplicationStreetLevel } from './layers/streetLevel.js';
 import { createInfrastructureLayers } from '../data/infrastructure.js';
 import { localGeoJsonServices } from './localGeojsonServices.js';
 import { createBhoteKoshiEventLayer } from '../data/bhoteKoshiEvent.js';
@@ -156,7 +156,7 @@ export function createApplicationCatalog({
           source: sources['fire-perimeters'],
         }),
         createApplicationAlpr({ surface, source: sources.alpr }),
-        createApplicationMapillary({ surface, source: sources.mapillary }),
+        createApplicationStreetLevel({ surface, source: sources.mapillary }),
         satellites,
         createApplicationLaunches({ source: sources.launches, satellites }),
         createApplicationTraffic({ source: sources.traffic }),