Skip rows with unknown PDG codes during predict

Checkpoints have a fixed PDG embedding vocab sized at train time, so a
code unseen during training has no embedding index. Drop those rows
and report a per-code skip count instead of raising a KeyError.

giant/cli.py

@@ -1,3 +1,4 @@
+from collections import Counter
 from enum import Enum
 from pathlib import Path
 from typing import Optional
@@ -344,13 +345,26 @@ def predict(
 
     writer: pq.ParquetWriter | None = None
     total = 0
+    skipped = 0
+    unknown_pdg_counts: Counter[int] = Counter()
     total_rows = sum(pq.ParquetFile(path).metadata.num_rows for path in files)
     chunk_iter = iter_file_chunks if coord == Coord.local else iter_cond_chunks
 
     bar = tqdm(total=total_rows, desc="predict", unit="row", dynamic_ncols=True)
     for path in files:
         for chunk in chunk_iter(path):
+            N_in = len(chunk["event_id"])
+
+            pdg_mask = np.array([int(p) in pdg_map for p in chunk["pdg"]])
+            if not pdg_mask.all():
+                unknown_pdg_counts.update(int(p) for p in chunk["pdg"][~pdg_mask])
+                chunk = {k: v[pdg_mask] for k, v in chunk.items()}
+
             N = len(chunk["event_id"])
+            skipped += N_in - N
+            if N == 0:
+                bar.update(N_in)
+                continue
 
             if coord == Coord.local:
                 cond_cont, cond_cat, target_raw, _, _ = build_features(
@@ -458,12 +472,20 @@ def predict(
                 writer = pq.ParquetWriter(out, table.schema)
             writer.write_table(table)
             total += N
-            bar.update(N)
+            bar.update(N_in)
 
     bar.close()
     if writer is not None:
         writer.close()
 
+    if skipped:
+        codes = ", ".join(
+            f"{pdg} ({count})" for pdg, count in sorted(unknown_pdg_counts.items())
+        )
+        typer.echo(
+            f"warning: skipped {skipped:,} row(s) with unknown PDG code(s): {codes}",
+            err=True,
+        )
     typer.echo(f"wrote {total:,} rows → {out}")