Release address-normalizer 2.0.0a2 under GPL-3.0

[shigabeev]

Summary

• ship the dependency-free v2 parser and conservative address-span detector as 2.0.0a2
• apply the exact GitHub GNU GPL v3 template and PEP 639 GPL-3.0-only package metadata
• record maintainer authorization and the reference-data/model provenance chain
• add a full Russian README alongside the English documentation
• enable gated TestPyPI/PyPI Trusted Publishing and GitHub release creation
• retain detailed failure diagnostics and independent evaluation domains

Product boundary

The package extracts unverified Russian address components and source offsets.
It does not bundle FIAS/GAR, validate address existence, return registry IDs,
geocode, or make runtime network requests.

Verification

• 74 unit tests passed
• strict mypy passed on 9 package modules
• 500-row historical gate passed: 95.8538% exact-component micro F1
• compact tagger gate passed: 96.5217% token accuracy, 94.2857% sequence accuracy, 96.8750% micro entity F1
• deterministic model regeneration passed; model is 37,130 bytes
• reproducible wheel and sdist builds are byte-identical across two builds
• wheel is 45,843 bytes and has no runtime dependencies
• artifact allowlist, negative policy tests, Twine metadata/rendering, and GPL release policy passed
• clean installed-wheel smoke tests passed on Python 3.10 and 3.14
• unrelated local notebooks were not added

Release

After CI passes, this PR is intended to be merged, tagged v2.0.0a2, rehearsed
on TestPyPI, and published unchanged to PyPI through Trusted Publishing.