bench: pass the resolved GLM engine path to eval_glm.py — cwd-relative ./glm default broke coli bench from other dirs (#203)

cmd_bench builds the eval_glm.py command but did not pass --glm,
so eval_glm.py fell back to ./glm which breaks when running from
any directory other than the source tree. Pass the already-resolved
GLM variable via --glm, matching --data and --snap.

Assisted-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

c/coli

@@ -585,7 +585,7 @@ def cmd_bench(a):
         print(f"  {C.dim}downloading missing datasets: {', '.join(missing)}{C.r}")
         subprocess.call([py, os.path.join(TOOLS,"fetch_benchmarks.py"),
                          "--out", a.data, "--tasks", ",".join(missing), "--limit", str(max(a.limit,200))])
-    cmd=[py, os.path.join(TOOLS,"eval_glm.py"), "--snap",a.model,
+    cmd=[py, os.path.join(TOOLS,"eval_glm.py"), "--glm", GLM, "--snap",a.model,
          "--tasks", tasks, "--limit", str(a.limit), "--data", a.data]
     if a.ram: cmd+=["--ram",str(a.ram)]
     e=env_for(a)