builder: search for its README

scripts/build_probe_testset.py

@@ -311,10 +311,22 @@ def main() -> int:
     manifest["n_runs"] = made
     manifest["n_probes"] = sum(p["n_probes"] for p in manifest["probes"])
     (out / "manifest.json").write_text(json.dumps(manifest, indent=1))
-    # The README is SOURCE, not output. It lived in the export directory once
-    # and the next rebuild's rmtree deleted it.
-    shutil.copy(Path(__file__).resolve().parents[1] / "docs" /
-                "probe_testset_README.md", out / "README.md")
+    # The README is SOURCE, not output — it lived in the export directory once
+    # and the next rebuild's rmtree deleted it. Searched rather than assumed:
+    # hard-coding the repo's docs/ made a clean-room rebuild die on a path that
+    # exists only here, which is the same failure calib_dir had.
+    here = Path(__file__).resolve().parent
+    for cand in (here.parents[0] / "docs" / "probe_testset_README.md",
+                 here / "docs" / "probe_testset_README.md",
+                 here.parent / "docs" / "probe_testset_README.md",
+                 Path.cwd() / "docs" / "probe_testset_README.md"):
+        if cand.is_file():
+            shutil.copy(cand, out / "README.md")
+            break
+    else:
+        print("  note: probe_testset_README.md not found; package built without "
+              "it. Fetch docs/probe_testset_README.md from the dataset to "
+              "include it.", flush=True)
     print(f"\n{manifest['n_probes']} probes over {made} start frames -> {out}")
     return 0 if made == args.runs else 1