feat(BNNBot): add wall distances for both bots to binary encoding (100 bits total)

8 new fields in ScanData (myWallN/S/E/W, enemyWallN/S/E/W), 7 bits each via Gray code,
appended after existing 44 bits. TOTAL_BITS 44 → 100.

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

BNNBot_garage/src/BNNBot.nim

@@ -36,11 +36,23 @@ method onScannedBot*(bot: BNNBot, e: ScannedBotEvent) =
   bot.hasLastPos = true
   bot.hasContact = true
 
+  let arenaW = getArenaWidth().float
+  let arenaH = getArenaHeight().float
+  let enemyX = e.x
+  let enemyY = e.y
   let scan = ScanData(
-    bearing:  bot.enemyBearing,
-    distance: bot.distance,
-    velocity: bot.velocity,
-    heading:  bot.heading,
+    bearing:    bot.enemyBearing,
+    distance:   bot.distance,
+    velocity:   bot.velocity,
+    heading:    bot.heading,
+    myWallN:    arenaH - by,
+    myWallS:    by,
+    myWallE:    arenaW - bx,
+    myWallW:    bx,
+    enemyWallN: arenaH - enemyY,
+    enemyWallS: enemyY,
+    enemyWallE: arenaW - enemyX,
+    enemyWallW: enemyX,
   )
   let vec = encode(scan)
   let hamming = if bot.hasPrev: hammingDistance(bot.prevVec, vec) else: 0