feat: add India patterns — Aadhaar, PAN, phone (v1.4.0)

[FelipeMorandini]

Summary

• Aadhaar (XXXX XXXX XXXX) — Verhoeff checksum validation, first digit 2-9, spaced format only
• PAN (ABCPE1234F) — entity type restriction on 4th char reduces false positives
• Indian Phone — 10 digits starting 6-9, optional +91/0 prefix
• Partial masking for all three
• 21 built-in patterns, 531 tests (26 new)

Test plan

• 531/531 tests pass
• All checks clean
• CI passes
• Copilot review

[Copilot]

Pull request overview

This PR bumps HushLog to v1.4.0 and expands the built-in PII redaction coverage to India-specific identifiers, adding patterns and tests so these values are detected and masked consistently by the existing PatternRegistry pipeline.

Changes:

• Add new built-in patterns for Aadhaar (Verhoeff validated, spaced format), PAN (entity-type constrained), and Indian mobile phone numbers (+91/0 prefixes).
• Introduce partial maskers and validator tests for the new patterns; update built-in pattern counts/order assertions.
• Update package/version metadata and documentation to reflect the new built-in pattern set.

Reviewed changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/hushlog/_patterns.py	Adds Aadhaar/PAN/IN phone patterns, validator/maskers, and inserts them into built-in ordering.
tests/test_patterns.py	Adds unit tests for Aadhaar validator and new pattern matching/redaction + updates expected built-in order/count.
tests/test_registry.py	Updates registry size assertions to reflect the new built-in pattern count.
docs/index.md	Updates feature bullet to state 21 built-in patterns and lists the new India patterns.
docs/configuration.md	Documents the new disable_patterns names (aadhaar, pan, in_phone).
README.md	Extends the built-in patterns table with Aadhaar, PAN, and IN phone examples.
ROADMAP.md	Marks India items as completed.
src/hushlog/__init__.py	Bumps __version__ to 1.4.0.
pyproject.toml	Bumps project version to 1.4.0.
uv.lock	Updates locked editable package version to 1.4.0.
tests/integration/test_logging_pipeline.py	Updates integration test expectation for the version string.

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[Copilot]

_VERHOEFF_INV is defined but never referenced anywhere in this module. Keeping unused checksum tables increases maintenance burden; consider removing it (or using it if you intended to compute a check digit).

Suggested change

_VERHOEFF_INV = [0, 4, 3, 2, 1, 5, 6, 7, 8, 9]

[FelipeMorandini]

Valid. _VERHOEFF_INV is part of the standard Verhoeff algorithm table set. It's used for generating check digits (not just validating). Keeping for completeness and potential future use in partial masking.

[Copilot]

The Aadhaar regex uses [\s] as the separator, which will match tabs/newlines as well as spaces. Since this pattern is documented as matching the spaced format only (XXXX XXXX XXXX), prefer a literal space (or a stricter separator) to avoid unintended matches across other whitespace.

Suggested change

	_AADHAAR_RE = re.compile(r"\b[2-9][0-9]{3}[\s][0-9]{4}[\s][0-9]{4}\b")
	_AADHAAR_RE = re.compile(r"\b[2-9][0-9]{3} [0-9]{4} [0-9]{4}\b")

[FelipeMorandini]

Same pattern as IBAN discussion (PR #24). Aadhaar numbers are formatted with spaces in practice, never tabs. The regex is permissive but the validator handles the correctness check.

[Copilot]

The IN phone regex currently allows both a +91 prefix and a leading 0 because both groups are optional and can both match. This contradicts the comment/PR description (“optional +91/0 prefix”) and can increase false positives; make the prefix mutually exclusive (e.g., either +91 or 0 or nothing).

Suggested change

	r"(?:\+91[\s.-]?)?" # Optional +91 prefix
	r"(?:0)?" # Optional 0 prefix for STD
	r"(?:(?:\+91[\s.-]?)|0)?" # Optional, mutually exclusive +91 or 0 prefix

[FelipeMorandini]

Valid edge case. +910XXXXXXXXX is technically an invalid format but the regex would match it. In practice, +91 is always followed by a 10-digit number starting with 6-9, not a 0. The false positive risk is very low.