node kit: alpha flag through train/eval, carry env+width fixes, bootstrap script

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

scripts/eval_carry.py

@@ -7,6 +7,7 @@ Grid entries are k:p pairs; k=0,p=0 is the plain baseline (same harness).
 
 import argparse
 import json
+import os
 import sys
 import time
 from pathlib import Path
@@ -20,7 +21,8 @@ from loop_common import (DIRECT_SUFFIX, BandLooper, MergeAdapter, chat_prompt,
 sys.path.insert(0, str(Path(__file__).resolve().parent.parent))
 from jlens.core import load_model  # noqa: E402
 
-OUT = Path(__file__).resolve().parent.parent / "results-loop"
+OUT = Path(os.environ.get("LOOP_OUT",
+    Path(__file__).resolve().parent.parent / "results-loop"))
 
 
 @torch.no_grad()
@@ -58,7 +60,8 @@ def main():
     model, tok = load_model(dtype=torch.bfloat16)
     tok.padding_side = "left"
     looper = BandLooper(model)
-    adapter = MergeAdapter().cuda()
+    adapter = MergeAdapter(
+        d=model.config.get_text_config().hidden_size).cuda()
     if args.adapter:
         adapter.load_state_dict(torch.load(args.adapter, map_location="cuda"))
         adapter.eval()