Drop .dev0 suffix: bump to 0.1.0 for first stable PyPI release

[mstorath]

Summary

Two-line version-string change so DCEBE actually ships a stable PyPI release.

• `pyproject.toml`: `0.1.0.dev0` → `0.1.0`
• `python/dcebe/init.py`: `version` and module docstring blurb

Why

The `v0.1.0` git tag triggered a release run that uploaded `dcebe-0.1.0.dev0` to PyPI. `pip install dcebe` skips dev versions by default, so users see "No matching distribution found". This PR drops the `.dev0` suffix so the next tag publishes `dcebe 0.1.0` proper.

Required follow-up after merge

The existing `v0.1.0` tag points at the old `0.1.0.dev0` commit. After merging this PR, force-replace the tag:

```sh
git tag -d v0.1.0
git push origin --delete v0.1.0
git checkout master && git pull
git tag -a v0.1.0 -m "First stable PyPI release"
git push origin v0.1.0
```

This is safe because no `dcebe 0.1.0` (proper) artifact exists on PyPI yet — only the orphan `0.1.0.dev0`. The new tag will trigger `release.yml` which uploads `dcebe-0.1.0` alongside the dev0 (PEP 440 ordering: `0.1.0.dev0 < 0.1.0`, so `pip install dcebe` resolves to the new one).

Test plan

• PR merged
• `v0.1.0` re-tagged at new master HEAD
• Release workflow ships `dcebe-0.1.0` to PyPI
• `pip install dcebe` works on a clean venv (without `--pre`)