**Ruff fixes:**
- Fix E702 in readers.py (multiple statements on one line)
- Add noqa comment for SIM115 in writers.py (intentional file keeping pattern)

**MyPy type fixes:**
- Fix audit.py: Use rule.id instead of rule.reason (attribute doesn't exist)
- Add @overload signatures for apply_policy() to properly type Union return
- Simplify TransformRegistry to avoid non-existent imports

**Key changes:**
- apply_policy() now has proper @overload for with_audit parameter
  - with_audit=False (default) returns str
  - with_audit=True returns tuple[str, list[AuditEvent]]
- This fixes type inference in CLI and other callers
- All 30 mypy errors should now be resolved

**Ruff fixes:**
- E701 in utils.py: Break if statements with inline returns
- E501 in base.py: Break long line in _open() function
- F401 in in_out/__init__.py: Add __all__ to indicate re-exports
- F403 in hide.py: Add noqa comments for wildcard import

**MyPy fixes:**
- transforms/registry.py: Remove None values from default dict
- hide.py: Add type annotation for __all__: list[str]

**Code cleanup:**
- Improved readability of conditional statements
- Proper module re-export declarations

**Core changes:**
- Clean up duplicate Detector protocol definitions in base.py
- Consolidate to single protocol using Finding (not Match)
- Remove duplicate Match dataclass and old registry system
- Add back simplified register() function for detector registration

**Detector updates:**
- EmailDetector: Use Finding instead of Match, remove labels attribute
- PhoneDetector: Update to Finding-based implementation, clean up signature
- HighEntropyTokenDetector: Remove duplicate shannon_entropy definition
- EntropyDetector: Use Finding instead of Match, remove labels
- All regex-based detectors in regexes.py already use Finding (no changes needed)

**Type improvements:**
- All detectors now properly implement Detector protocol
- Consistent return type: Iterable[Finding]
- Removed context parameter from detector.detect() signature (v0.1 simplification)

Resolves mypy type errors for detector implementations and protocol compliance.

**Type fixes:**
- Add type: ignore to yaml assignment (yaml can be None in except clause)
- Fix .strip() calls on potentially None values
  - Store get() result in temporary variable before isinstance check
  - Ensures mypy sees consistent type through isinstance narrowing
- Applied to: name, description fields

**Pattern:**
Instead of: if isinstance(dict.get(key), str) and dict.get(key).strip():
Changed to:
    value = dict.get(key)
    if isinstance(value, str) and value.strip():

This ensures type narrowing works correctly with mypy.

Major changes:
- Updated all detector files (ssn, nhs, iban, credit_card) to use Finding instead of Match
- Removed context parameter from all detector detect() methods
- Fixed E701 errors (multiple statements on one line) in ssn.py and utils.py
- Fixed E501 line length issue in regexes.py
- Fixed SIM103/SIM102 errors in credit_card.py and ssn.py
- Removed unused Match, all_detectors, detectors_for, get imports from detectors/__init__.py
- Fixed EmailNotValidError duplicate definition in regexes.py
- Updated policy/loader.py to fix type narrowing issue
- Updated pyproject.toml to use lint.select instead of deprecated select
- Updated __init__.py to use contextlib.suppress for ImportError handling
- Run.py updated to remove context parameter and use Finding instead of Match
- All mypy and ruff checks now pass

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018vfBCwNVrttAUtpqcHcM6N

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018vfBCwNVrttAUtpqcHcM6N