[Bug] Can't filter geojson column mode points by polygon

[leverglowh]

Describe the bug
When filtering by drawing a polygon or rectangle, it has no effect on point layers with column mode geojson.
This is happening because

1. inside the function geojsonPosAccessor in the file point-layer.ts, d is normally an array, so accessing the position value with d[geojson.fieldIdx] works and returns a string "POINT (yy xx)".
   But when I click filter, and the function is called from filter-utils.ts line 387, d is an object with this structure: { index: 0, dataContainer: {...} }, leading to pos being undefined.
2. Even if we arrive at line 387 in filter-utils.ts with the geojson value, say like this:

   export const geojsonPosAccessor =
     ({geojson}: {geojson: LayerColumn}) =>
     d => {
       if (Array.isArray(d)) {
         return d[geojson.fieldIdx];
       } else if (typeof d === 'object' && d.dataContainer) {
         return d.dataContainer.valueAt(d.index, geojson.fieldIdx);
       }
     };

   it still expects an array of coordinates, throwing Uncaught TypeError: pos.every is not a function on the same line.
   A solution could be just extract the coordinates from the geojson string using regex, something like

   // Vibe coding solution warning
   if (isPointGeometry) {
     // Parse "POINT (lng lat)"
     const match = geometry.match(
         /POINT\s*\(\s*([-+]?[0-9]*\.?[0-9]+)\s+([-+]?[0-9]*\.?[0-9]+)\s*\)/
     );
     if (!match) return;
     lng = parseFloat(match[1]);
     lat = parseFloat(match[2]);
   }

   But it's ugly, so here I am.
   Maybe we can add an ad hoc helper function inside the point layer class to get the coordinates?
   Thoughts?

To Reproduce
Steps to reproduce the behavior:

1. Create a simple csv like this:

   point
   POINT (7.63 45.04)
   POINT (10.07 45.82)
   

2. Import into kepler using add data modal
3. Change the layer type from geojson to point, and make sure it uses column "point" in geojson mode
4. Draw a rectangle around a point, right click it and select the layer
5. See error in console: Uncaught TypeError: can't access property "every", pos is undefined on line 387 of filter-utils.ts

Expected behavior
It should correctly filter points without throwing errors.

Screenshots
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Additional context
Reproduced in all demo websites and locally.