fix(frank-large): verify exactly the fetched file set, not the whole Hub tree

The verification looped over every LFS file under UD-IQ4_XS/ and MTP/ in
the live Hub tree — the five MTP head variants we do not fetch (BF16,
Q4_K_M, Q8_0, shared-BF16, shared-Q4_K_M) printed MISSING, set ok=False,
and set -e killed the script silently between verification and assembly
after a 3-hour download. Verify exactly the FILES set instead (passed to
python as argv), and report NOT IN HUB TREE when an expected file has
vanished upstream. Also fix the layout comment: the transport parts live
in UD-IQ4_XS/, not parts/.

scripts/download-frank-large-unsloth.sh

@@ -22,7 +22,7 @@
 #   Qwen3.8-Flash-Next-UD-IQ4_XS.gguf             93,682,584,224  main model
 #   mtp/mtp-Qwen3.8-Flash-Next-shared-Q8_0.gguf   2,786,568,256  draft head
 #   vision/mmproj-F16.gguf                         904,004,000  projector
-#   parts/  the three verified transport parts (kept for --verify-only)
+#   UD-IQ4_XS/  the three verified transport parts (kept for --verify-only)
 #   SHA256SUMS
 set -euo pipefail
 
@@ -57,15 +57,17 @@ FILES=(
     "mmproj-F16.gguf 904004000 1f7b7f0b984cf065c604360c29c8098362ed61b290db0ff12c6f360bb1a8a980"
 )
 
-if [[ "$mode" == "download" ]]; then
-    for line in "${FILES[@]}"; do
-        read -r rel size _ <<<"$line"
+RELS=()
+for line in "${FILES[@]}"; do
+    read -r rel size _ <<<"$line"
+    RELS+=("$rel")
+    if [[ "$mode" == "download" ]]; then
         dl "$rel"
-    done
-fi
+    fi
+done
 
 echo "verifying parts against the live Hub tree API"
-python3 - "$MODEL_DIR" "$REPO" <<'PY'
+python3 - "$MODEL_DIR" "$REPO" "${RELS[@]}" <<'PY'
 import hashlib, json, os, sys, urllib.request
 
 model_dir, repo = sys.argv[1], sys.argv[2]
@@ -84,9 +86,11 @@ def sha256(path):
     return h.hexdigest()
 
 ok = True
-for rel, (size, oid) in sorted(want.items()):
-    if not rel.startswith(("UD-IQ4_XS/", "MTP/")) and rel != "mmproj-F16.gguf":
-        continue
+expected = set(sys.argv[3:])
+for rel in sorted(expected):
+    if rel not in want:
+        print(f"NOT IN HUB TREE {rel}"); ok = False; continue
+    size, oid = want[rel]
     path = os.path.join(model_dir, rel)
     if not os.path.isfile(path):
         print(f"MISSING {rel}"); ok = False; continue