fix(normalizer): strip mailto: prefix and query params from email targets (#353)

[DYNOSuprovo]

Summary

Closes #353.

When pasting an email target such as mailto:someone@example.com or mailto:a@b.com?subject=hi, the mailto: prefix survived into the scan target string and was passed down to underlying email reconnaissance modules.

This change keeps both normalizers (cli.py on the backend and frontend/src/lib/scan-target.ts on the frontend) in sync:

• Case-insensitively strips leading mailto: prefixes (mailto:, MAILTO:).
• Drops query parameter strings following ? (e.g., ?subject=x).
• Preserves downstream email casing normalization (lowercased) and scan type detection (email).

Changes Made

1. cli.py (normalize_target):

   • Strips leading case-insensitive mailto: prefix.
   • Drops anything after ? to cleanly extract the email address.

2. frontend/src/lib/scan-target.ts (normalizeScanTarget):

   • Mirrors the same mailto: and query parameter stripping logic before scheme and domain normalization.

3. frontend/scripts/test-scan-target.mjs:

   • Updates normalizeScanTarget test assertions to verify that mailto: is stripped rather than retained.
   • Adds test cases for mailto:a@b.com?subject=x and case-insensitive query parameter handling.
   • Verifies detectScanType correctly recognizes mailto:a@b.com?subject=x as 'email'.

4. tests/test_cli_target_normalization.py:

   • Adds test cases in test_normalize_target verifying mailto:user@example.com, MAILTO:USER@EXAMPLE.COM, mailto:a@b.com?subject=x, and mixed-case query strings all resolve to clean lowercased email addresses.
   • Adds test_detect_type assertions for mailto: inputs.

Verification

• node scripts/test-scan-target.mjs in frontend/: Passed (scan target normalization tests passed).
• All frontend test suites (test:urls, test:i18n, test:i18n-lookup, test:scan-target, test:encoder): Passed.
• TypeScript check (tsc --noEmit src/lib/scan-target.ts): Passed with 0 errors.
• pytest tests/test_cli_target_normalization.py: 20 passed.
• Full pytest test suite (pytest tests/ -q): All 393 tests passed.
• Flake8 critical rules check (flake8 --count --select=E9,F63,F7,F82): 0 errors.
• DCO: Commit signed off per Developer Certificate of Origin (git commit -s).

[github-actions]

Thanks for the first pull request here. CI needs a maintainer to approve the run before it starts, so it may sit for a bit before anything happens. pytest tests/ -q passing is the main thing I look at.

[NovaCode37]

Merged, closes #353. Both normalizers stay in step, and you updated the existing test that asserted the prefix was kept rather than just adding new ones, which is the part people usually miss. Checked it together with #358, since both touch cli.py: they merge cleanly and the full suite passes.