fix(gun_harness): bump virtual bullet ring buffer 512→2048

With 12 guns × 4 power bins = 48 bullets/tick, 512 slots overflow
before slow bullets resolve (~36 ticks travel). 2048 gives headroom.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

common_libs/gun_harness/virtual_bullets.nim

@@ -9,7 +9,7 @@ import gun_interface
 const
   PowerBins*    = [1.0, 1.5, 2.0, 3.0]  ## 4 bins; ponytail: fixed array, add runtime config if needed
   WindowSize*   = 50                      ## rolling window ticks for fitness
-  MaxBullets*   = 512                     ## hard cap; ponytail: ring buffer, resize if more guns added
+  MaxBullets*   = 2048                    ## hard cap; ponytail: ring buffer, resize if more guns added
   MinHitRate*   = 0.40                    ## 40% threshold for acceptable power selection
 
 type