feat(SAC_LSTM_Bot): training harness (#49)

sac_train.sh orchestrates chunked self-play via tools/training_runner/
RunTraining.java: weighted opponent sampling per chunk, deterministic
eval (SACLSTM_EVAL_MODE=1) every N chunks with win-rate tracking, best
checkpoint (weights/sac_best.zip) by eval score, crash-restart loop on
the runner's liveness detection.

Supporting changes:
- integration.nim: opponentKey() keys the NewBattle buffer-clear rule on
  getBotName(id) with numeric-id fallback (#49 Q14 follow-up);
  bumpRoundCounter() emits the per-round liveness signal.
- SAC_LSTM_Bot.nim: onRoundEnded -> bumpRoundCounter().
- RunTraining.java: BOT_NAME env parameterizes result matching
  (default PPO_Bot, unchanged behavior for PPO).
- Launch packaging: root SAC_LSTM_Bot.json + .sh for the booter;
  src json name aligned to 'SAC_LSTM_Bot' so self-reported identity
  matches the booted identity (mismatch = runner connect timeout).

SAC_LSTM_Bot/SAC_LSTM_Bot.json

@@ -0,0 +1,11 @@
+{
+  "name": "SAC_LSTM_Bot",
+  "version": "0.1.0",
+  "authors": ["Davide Cappellini"],
+  "description": "SAC+LSTM-trained Tank Royale bot (#37) — training/eval launch config",
+  "homepage": "",
+  "countryCodes": ["IT"],
+  "gameTypes": ["classic", "melee", "1v1"],
+  "platform": "Nim",
+  "programmingLang": "Nim"
+}