feat(street-level): IMAGERY and SINCE filters for KartaView

KartaView filters coverage on its server only in its PNG tiles (its JSON
tiles come back empty with a filter), so a filtered tile's PNG is a mask
over the cached JSON segments: a segment stays when at least half the
points along it lie on drawn pixels. A filter change reloads the lines
(lineCoverage.reload keeps the drawn ones until the new ones are in);
masks are cached per filter and tile, and a filtered tile KartaView is
still drawing (504 or a timeout) is asked again, four tries in all.
The nearest lookup asks the photo API for the projection and date, and
the cones follow the filter like Mapillary's. The gate fixture draws
filtered PNG tiles and adds an older flat-only street; a new gate step
checks 360 and LAST YEAR thin KartaView's lines and ALL brings them back.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/layers/streetLevel/lineCoverage.js

@@ -798,6 +798,15 @@ export function createLineCoverage({
     notify();
   }
 
+  /**
+   * Load every tile again (a source that filters on its server had its
+   * filter changed); the lines drawn now show until the new ones are in.
+   */
+  function reload() {
+    retire();
+    refresh();
+  }
+
   /**
    * Redraw tiles draped or cast for the new surface mode, then re-pick the
    * zoom, since the ground height under the camera may have changed.
@@ -919,6 +928,7 @@ export function createLineCoverage({
     clear,
     resetErrors,
     rebuild,
+    reload,
     setSurface,
     recolorSequence,
     sequenceCount,