chore: import upstream snapshot with attribution

tools/check_docs_github_links.py

@@ -0,0 +1,81 @@
+#!/usr/bin/env python3
+import argparse
+import re
+from pathlib import Path
+from typing import NamedTuple
+
+
+class Violation(NamedTuple):
+    path: Path
+    line_number: int
+    ref: str
+    url: str
+
+
+def _compile_link_pattern(repo_slug):
+    escaped_repo = re.escape(repo_slug)
+    return re.compile(
+        rf"https://github\.com/{escaped_repo}/(?:blob|tree)/(?P<ref>[^/\s)\]\"'<>]+)"
+        rf"(?P<rest>/[^\s)\]\"'<>]*)?"
+    )
+
+
+def find_forbidden_links(root, repo_slug, forbidden_refs):
+    root = Path(root)
+    forbidden_refs = set(forbidden_refs)
+    link_pattern = _compile_link_pattern(repo_slug)
+    violations = []
+
+    for path in sorted(root.rglob("*.md")):
+        if not path.is_file():
+            continue
+        for line_number, line in enumerate(
+            path.read_text(encoding="utf-8").splitlines(), 1
+        ):
+            for match in link_pattern.finditer(line):
+                ref = match.group("ref")
+                if ref in forbidden_refs:
+                    violations.append(
+                        Violation(
+                            path=path,
+                            line_number=line_number,
+                            ref=ref,
+                            url=match.group(0),
+                        )
+                    )
+    return violations
+
+
+def main(argv=None):
+    parser = argparse.ArgumentParser(
+        description="Reject docs links that point to moving GitHub source refs."
+    )
+    parser.add_argument("--root", default="docs", help="Directory to scan.")
+    parser.add_argument(
+        "--repo-slug", required=True, help="Example: PaddlePaddle/PaddleOCR"
+    )
+    parser.add_argument(
+        "--forbidden-ref",
+        action="append",
+        required=True,
+        help="Moving source ref to reject. Can be passed multiple times.",
+    )
+    args = parser.parse_args(argv)
+
+    violations = find_forbidden_links(
+        args.root,
+        repo_slug=args.repo_slug,
+        forbidden_refs=set(args.forbidden_ref),
+    )
+    if violations:
+        for violation in violations:
+            print(
+                f"{violation.path}:{violation.line_number}: "
+                f"forbidden GitHub ref '{violation.ref}' in {violation.url}"
+            )
+        return 1
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())