[doc] Add contributing.md and codeowners.

[Seven-Streams]

This PR adds the CONTRIBUTING.md and CODEOWNERS for the repo.

[Copilot]

Pull request overview

This PR adds contributing guidelines and code ownership documentation to the XGrammar repository. The changes establish processes for community contributions, code review, and maintainership.

• Introduces CONTRIBUTING.md with PR naming conventions, review process, and community guidelines
• Adds CODEOWNERS file mapping repository files to responsible maintainers
• Includes utility scripts to generate and maintain the CODEOWNERS file

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 23 comments.

Show a summary per file

File	Description
CONTRIBUTING.md	Establishes contribution workflow, PR conventions, and review process
.github/CODEOWNERS	Maps 226 files to code owners for review assignments
.github/name_mappings.csv	Provides git-to-GitHub username mappings for code owner generation
scripts/generate_code_owner.bash	Bash script to automate CODEOWNERS file generation from git history
scripts/name_replace.py	Python utility to replace names in CODEOWNERS using CSV mappings

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[Copilot]

Missing input validation and error handling. The script will crash with IndexError if insufficient command-line arguments are provided. Consider adding a check like if len(sys.argv) != 3: and printing usage instructions.

Suggested change

	if __name__ == "__main__":
	if __name__ == "__main__":
	if len(sys.argv) != 3:
	print(f"Usage: {sys.argv[0]} <csv_file> <input_file>", file=sys.stderr)
	sys.exit(1)

[Copilot]

Missing error handling for file operations. If the input file doesn't exist or isn't readable, the script will crash with an unhelpful error. Consider wrapping file operations in try-except blocks with informative error messages.

Suggested change

	with open(input_file, "r", encoding="utf-8") as f:
	content = f.read()
	with open(csv_file, "r", encoding="utf-8") as f:
	reader = csv.reader(f)
	next(reader, None)
	for old, _, new in reader:
	content = content.replace(old, new)
	with open(input_file, "w", encoding="utf-8") as f:
	f.write(content)
	try:
	with open(input_file, "r", encoding="utf-8") as f:
	content = f.read()
	except (FileNotFoundError, PermissionError, OSError) as e:
	print(f"Error opening or reading input file '{input_file}': {e}", file=sys.stderr)
	sys.exit(1)
	try:
	with open(csv_file, "r", encoding="utf-8") as f:
	reader = csv.reader(f)
	next(reader, None)
	for old, _, new in reader:
	content = content.replace(old, new)
	except (FileNotFoundError, PermissionError, OSError) as e:
	print(f"Error opening or reading CSV file '{csv_file}': {e}", file=sys.stderr)
	sys.exit(1)
	try:
	with open(input_file, "w", encoding="utf-8") as f:
	f.write(content)
	except (PermissionError, OSError) as e:
	print(f"Error writing to input file '{input_file}': {e}", file=sys.stderr)
	sys.exit(1)

[Copilot]

CSV unpacking assumes exactly 3 columns per row. If the CSV has a different number of columns, this will raise a ValueError. Consider validating row length or using more defensive unpacking.

Suggested change

	for old, _, new in reader:
	for row in reader:
	if len(row) < 3:
	continue # Skip rows with insufficient columns
	old, _, new = row[:3]

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	.gitmodules @Ubospica @Ubospica
	.gitmodules @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	cpp/grammar_builder.h @Ubospica @Ubospica
	cpp/grammar_builder.h @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	python/xgrammar/kernels/apply_token_bitmask_inplace_cuda.py @Ubospica @Ubospica
	python/xgrammar/kernels/apply_token_bitmask_inplace_cuda.py @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	python/xgrammar/kernels/apply_token_bitmask_inplace_triton.py @Ubospica @Ubospica
	python/xgrammar/kernels/apply_token_bitmask_inplace_triton.py @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	tests/python/test_grammar_matcher_ebnf.py @Ubospica @Ubospica
	tests/python/test_grammar_matcher_ebnf.py @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	tests/python/test_grammar_matcher_json.py @Ubospica @Ubospica
	tests/python/test_grammar_matcher_json.py @Ubospica

[Copilot]

Duplicate code owner '@Ubospica' specified for the same file. This appears to be a redundant entry.

Suggested change

	tests/python/test_grammar_matcher_json_schema.py @Ubospica @Ubospica
	tests/python/test_grammar_matcher_json_schema.py @Ubospica