Stream-Mapparr 1.26.1791529

Shared matcher core migration

The drifting per-plugin fuzzy_matcher.py is retired. The pure matching primitives now live once in a shared FuzzyMatcherCore, vendored byte-identically into the inner folder as matching_core.py; FuzzyMatcher subclasses it and keeps only Stream-Mapparr's plugin-specific layer (zone routing, OTA callsign resolution, channel-DB loading). Stream-Mapparr was the migration canary.

• Vendored core is sha256-pinned (scripts/core_manifest.json) and enforced by a parity gate (tests/test_core_parity.py) + golden gate (tests/test_matcher_golden.py) in CI; .gitattributes pins it to LF. matching_core.py ships with the code — the plugin won't load without it.
• strip_bare_region is a class-attr opt-in (off here — preserves bug-066 behavior).
• calculate_similarity uses a Python >= min_ratio gate (replacing rapidfuzz score_cutoff); no change to live match decisions.

Normalization (ported from Lineuparr PR #13)

• Non-ASCII names no longer collapse to empty in process_string_for_matching (NFKD-fold, keep alphanumerics).
• Unicode box-bar delimiters (┃ / │) recognized for prefix stripping.

Packaging built with git archive (bug-087-safe forward-slash paths), validated with scripts/validate_zip.py (matching_core.py included).