[Makiras]

Publish the new Toffee implementation as uc-toffee, with uc-xcomm>=1.1,<2 installed as a normal runtime dependency. Python imports remain toffee, and the toffee / toffee-coverage-report commands are unchanged. Legacy master and the old pytoffee distribution remain independent.

• Rename distribution metadata, artifact validation, CLI installation hints and documentation to uc-toffee.
• Build and test against a pinned xcomm backend, and verify its package version, native ABI and coverage protocol.
• Start the new main release history at v2.0.0, avoiding collisions with Legacy 0.x tags. Preserve retry behavior, provenance checks and subsequent patch/minor/major increments.
• Publish the exact verified wheel and sdist to PyPI through release.yml, using Trusted Publishing with environment pypi.
• Use matching README badges and absolute documentation links; update installation instructions for the PyPI release and retain the final Legacy notice.

Validation at 3ff64672cfd35f5e48a624af211289aaa818fa51:

• Clean Python 3.12 environment with a locally built 2.0.0 candidate and the actual PyPI uc-xcomm==1.1.0: 1,163 tests and 3 subtests passed with --require-xspcomm; pip check, ABI 3 and coverage protocol 5 checks passed.
• Actual PyPI uc-picker==2.2.0, uc-xcomm==1.1.0 and swig==4.5.1 generated and compiled an Adder using system CMake and Verilator. The candidate Toffee drove sum, carry and overflow cases successfully.
• Final wheel/sdist passed strict Twine checks, version/name/template validation and manifest checksum verification. Strict MkDocs build and documentation tests passed; all 20 existing README destinations/images returned HTTP 200. The new PyPI project and its version badge are verified after publication.
• Release tests cover independent Legacy history, initial version selection, retries, collisions and subsequent increments.

The repository default branch is main. Merging this PR starts the uc-toffee==2.0.0 release, subject to the tagged workflow's full checks. PyPI receives one py3-none-any wheel and one source distribution; the provenance manifest and checksums remain on GitHub Release.
GitHub CI on the final PR commit passed Python 3.11/3.12, strict docs, package validation, sdist rebuild and isolated installation.