feat(mapillary): street-level layer core — coverage, sequences, viewer bridge, query engine

Camera-driven Mapillary coverage (z0–5 overview points from orbit, z11–14
ground-clamped sequence lines below 60 km), per-sequence image cones, an
embedded MapillaryJS viewer bridge with a camera-follow mode, sprite icons
for map features, and a query engine that turns a plan into a streamed
z14 tile fan-out. Registers an on-globe CC BY-SA 4.0 credit while enabled.

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

server/providers/local.js

@@ -19,6 +19,7 @@ import { aisLiveProxy } from './vessels/ais-live.js';
 import { trackBackfillProxies } from './aircraft/tracks.js';
 import { openAiRealtimeProxy } from './openai.js';
 import { googlePlacesContextProxy } from './places.js';
+import { mapillaryProxy } from './mapillary.js';
 import { keySetupEndpoint } from '../standalone/key-setup.js';
 
 /** Construct the local provider plugins in their established order. */
@@ -45,6 +46,7 @@ function localProviderPlugins() {
     trackBackfillProxies(),
     openAiRealtimeProxy(),
     googlePlacesContextProxy(),
+    mapillaryProxy(),
     keySetupEndpoint(),
   ];
 }