Add GitHub code-search discovery, tests, and CI for subdomain_searcher

[Mankeluvsit]

Motivation

• Improve passive discovery coverage by surfacing hardcoded hostnames found in public code repositories.
• Make the tool more robust and maintainable by adding unit tests and a CI workflow to catch regressions.

Description

• Add discover_from_github(domain, github_token=None) which queries the GitHub code search API and extracts hostnames using existing HOSTNAME_RE.
• Wire GitHub results into the main aggregation pipeline and add a --github-token CLI flag for higher API limits.
• Update README.md usage and method list to include GitHub code search and a tokenized example command using --github-token.
• Add unit tests in tests/test_subdomain_searcher.py covering normalize_domain, discover_from_crtsh, discover_from_homepage, discover_bruteforce, discover_from_github, and load_wordlist.
• Add a GitHub Actions workflow at .github/workflows/subdomain-searcher-tests.yml to run pytest on pushes and PRs touching the tool or tests.

Testing

• Ran pytest -q locally; all tests passed (6 passed).
• Executed python3 subdomain_searcher.py example.com --json to validate runtime behavior and JSON output; the command completed successfully.
• CI workflow added to run the same pytest steps on push and pull requests to keep tests enforced.

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Codex Task

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Extract hostnames from matched code snippets

This loop builds text from metadata fields (name, path, html_url, repo name) rather than matched file content, so for typical code-search hits where the hostname appears only inside the file body, HOSTNAME_RE finds nothing and the GitHub source silently returns near-empty results. To make this feature work as intended, parse matched fragments (for example via text_matches) or fetch file contents before running hostname extraction.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Enforce label boundary when filtering by domain suffix

Using candidate.endswith(domain) accepts unrelated hostnames that merely share trailing characters (for example, badexample.com when scanning example.com), which can pollute results with false positives whenever such strings are present in search output. The filter should require an actual DNS boundary, e.g. exact match or '.' + domain suffix.

Useful? React with 👍 / 👎.