Fix CI version check and verify Pages deployment

[nekrasovp]

What changed

• replace the hard-coded 0.1.0 wheel smoke assertion with consistency checks across pyproject.toml, installed package metadata, and predxt.__version__
• verify the deployed GitHub Pages URL with bounded retries and a stable <title>predxt</title> marker

Why

CI run 6 built version 0.2.0 successfully but failed its final wheel smoke test because the workflow still expected 0.1.0. The Pages deployment itself succeeds, so the workflow now verifies the published endpoint after deployment.

Impact

No SDK API, documentation content, package version, or hosting-platform changes.

Validation

• actionlint .github/workflows/ci.yml .github/workflows/pages.yml
• uv run ruff check .
• uv run mypy
• uv run pytest -q -s (49 passed)
• uv build
• uv run twine check dist/*
• uv run mkdocs build --strict
• isolated wheel installation and version consistency check (0.2.0)