fix(ores): pass whitelist to set_block_absolute so STONE actually gets overwritten

The previous ore placement called set_block_absolute(ore, x, y, z, None, None)
which silently no-ops over any non-AIR block. set_block_with_properties_absolute
at mod.rs:892 routes to an else { false } branch when there is an existing block
and no filters are given. So every vein step that landed on stone was a no-op.

Passing Some(&[STONE]) as the whitelist makes the existing-block path match and
write. The earlier check_for_block_absolute pre-gate is kept because, when the
target cell is AIR, the same function's else { true } branch would otherwise
write ore into the air above the surface.

Author: louis-e

src/ore_generation.rs

@@ -110,8 +110,7 @@ pub fn generate_ores(editor: &mut WorldEditor, xzbbox: &XZBBox) {
     }
 }
 
-// 3D random walk that replaces STONE only — any other block ends the placement
-// at that step (next step continues from the new position).
+// Whitelist on set_block_absolute is required to overwrite STONE; pre-check filters AIR.
 fn place_vein(
     editor: &mut WorldEditor,
     block: Block,
@@ -124,7 +123,7 @@ fn place_vein(
     let (mut cx, mut cy, mut cz) = (x, y, z);
     for _ in 0..size {
         if editor.check_for_block_absolute(cx, cy, cz, Some(&[STONE]), None) {
-            editor.set_block_absolute(block, cx, cy, cz, None, None);
+            editor.set_block_absolute(block, cx, cy, cz, Some(&[STONE]), None);
         }
         match rng.random_range(0..6) {
             0 => cx += 1,