feat(street-level): KartaView's SINCE is its upload date, noted in the panel

KartaView's server filters by upload date only, so SINCE goes by it
throughout for KartaView: the lines (as before), the photo a click opens
and the cones, the cut-off taken as its UTC day as KartaView's startDate
(passesKartaViewFilter). Providers may declare sinceBasis: 'upload'
(validated); while one is lit the panel shows "KartaView: by upload date"
under the SINCE slider, read out with it. The gate checks the note, and
step 13's picks get 60 s on a loaded machine.

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

src/layers/streetLevel/registry.test.mjs

@@ -117,4 +117,9 @@ test('a provider may narrow the filters it honours and pick a view-cone marker',
     () => validateProviders([def({ marker: { kind: 'pegman' } })]),
     /marker must be/,
   );
+  validateProviders([def({ sinceBasis: 'upload' })]);
+  assert.throws(
+    () => validateProviders([def({ sinceBasis: 'shot' })]),
+    /sinceBasis must be 'capture' or 'upload'/,
+  );
 });