Keep the brute's torn-off arm on one side

The generator drew the second frame of that wound stage as a MIRROR of the first,
so the missing arm and the dragged pole swapped sides on every step — which is
the "wound on the left arm on one foot but not the other" Oliver saw, and it was
on the sheet, not in the frame assignment. Flipping the frame back puts the
injury where it belongs, and a horizontal flip IS the leg swap a second stride
frame wants, so the walk still reads.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

index.html

@@ -97,6 +97,6 @@
     <p id="build"></p>
   </div>
 </div>
-<script type="module" src="main.js?v=72"></script>
+<script type="module" src="main.js?v=73"></script>
 </body>
 </html>

render.js

@@ -155,7 +155,7 @@ export function proj(x, y, z) {
 
 // ---------------------------------------------------------------- sprites ----
 // assets/<name>.png; game falls back to code-drawn figures until sprites load.
-const SPRV = 65; // asset cache-buster — bump with main.js?v=N (see the img.src note below)
+const SPRV = 66; // asset cache-buster — bump with main.js?v=N (see the img.src note below)
 const SPR = {};
 for (const n of ['p_idle1','p_idle2','p_bounce','p_bounce2','p_toss','p_smash','p_run1','p_run2','p_run3','p_run4','p_swing1','p_swing2','p_die1','p_die2','p_die3','p_die4','p_die5',
                  'o_idle1','o_idle2','o_bounce','o_bounce2','o_toss','o_smash','o_run1','o_run2','o_swing1','o_swing2',