fix(catalog): prevent unnecessary list reloads on map movement

- Remove currentMapBounds from watch - it changes on every map move
- Watch only filterByBounds and urlBounds (URL-based state)
- Add early return in setBoundsFilter if bounds haven't changed

This fixes the issue where the list was reloading on every map movement
even when the 'filter by bounds' checkbox was OFF.

app/composables/useCatalogSuppliers.ts

@@ -101,6 +101,17 @@ export function useCatalogSuppliers() {
   }
 
   const setBoundsFilter = (bounds: { west: number; south: number; east: number; north: number } | null) => {
+    // Early return if bounds haven't changed
+    const prev = filterBounds.value
+    const same = prev === bounds || (
+      prev && bounds &&
+      prev.west === bounds.west &&
+      prev.south === bounds.south &&
+      prev.east === bounds.east &&
+      prev.north === bounds.north
+    )
+    if (same) return
+
     filterBounds.value = bounds
     if (isInitialized.value) {
       fetchPage(0, true)