chore(release): conclave-cli distribution + OIDC publish workflow + dep audit

[ernestprovo23]

PR-A of the conclave v1.0 release: distribution + release-engineering.
Implements readiness-review must-dos #1 (distribution + publish workflow), #2
scaffolding (release runbook; the version bump + CHANGELOG land in the release
commit, not here), and #6 (pip-audit in CI).

What changed

1. Distribution rename → conclave-cli

The PyPI name conclave is taken by an unrelated project (a blockchain client).

• pyproject.toml [project].name → conclave-cli. Command (conclave),
  import package (conclave), and repo all unchanged. Added [project.urls].
  Version left at 0.3.0 — the 1.0.0 bump is the release commit (see RELEASING.md).
• README install → pip install conclave-cli, with a short note documenting the
  install-name vs command/import split, and that the PyPI conclave package is an
  unrelated project. Editable source install kept for development.
• Verified: python -m build now emits conclave_cli-0.3.0{.tar.gz,-py3-none-any.whl}.

2. OIDC publish workflow — .github/workflows/release.yml

• Trigger on: release: published (a pushed tag alone does nothing).
• Jobs: build (python -m build sdist+wheel → artifact) → pypi-publish
  (pypa/gh-action-pypi-publish, OIDC Trusted Publishing, no stored token, PEP 740
  attestations) → sign (sigstore/gh-action-sigstore-python keyless; signs
  sdist+wheel, attaches .sigstore bundles to the Release; self-verifies).
• Every uses: SHA-pinned with a # vX.Y.Z comment.
• Top-of-file comment: inert until a Release is published AND the conclave-cli
  Trusted Publisher is configured.

Action	Pin (commit SHA)	Tag
actions/checkout	11bd71901bbe5b1630ceea73d27597364c9af683	v4.2.2
actions/setup-python	a26af69be951a213d495a4c3e4e4022e16d87065	v5.6.0
actions/upload-artifact	ea165f8d65b6e75b540449e92b4886f43607fa02	v4.6.2
actions/download-artifact	d3f86a106a0bac45b974a628896c90dbdf5c8093	v4.3.0
pypa/gh-action-pypi-publish	cef221092ed1bacb1cc03d23a2d87d1d172e277b	v1.14.0
sigstore/gh-action-sigstore-python	5b79a39c381910c090341a2c9b0bf022c8b387e1	v3.4.0

3. pip-audit in CI — fail-closed

New audit job in test.yml runs pip-audit --skip-editable against resolved
deps and fails CI on a known vuln. Rationale: conclave is security-positioned,
the dep surface is tiny (httpx + a few well-maintained libs) so false-positive
churn is low, and there is an --ignore-vuln escape hatch documented in RELEASING.md.
Currently: no known vulnerabilities.

4. Dependency lockfile

requirements-dev.lock — hash-pinned dev + runtime tree via
uv pip compile --universal --generate-hashes --python-version 3.11 --extra dev pyproject.toml -o requirements-dev.lock.

5. RELEASING.md runbook

One-time PyPI Trusted-Publisher setup for conclave-cli, cut-a-release checklist
(bump version→1.0.0 in both pyproject.toml and src/conclave/__init__.py,
finalize CHANGELOG, tag, publish Release), post-release verification (Sigstore
bundle, PEP 740 attestations), rollback/yank.

6. Test-infra fix (CI unblock)

tests/test_logging.py asserted an exact len(logger.handlers) == 1. Under
pytest 9.1.0 the logging plugin attaches LogCaptureHandlers to every logger,
inflating the count to 3 and failing CI (and a fresh local resolve) independent of
source changes. The two assertions now count only conclave's own handler, excluding
pytest's capture handlers — preserving intent, robust to the runner. Production
logging is unchanged (outside pytest it installs exactly one StreamHandler).

Owner action required (one-time, manual)

Configure the conclave-cli PyPI Trusted Publisher before the first release
(RELEASING.md §0). Until then the publish job fails closed — nothing is published.

Invariants

ruff check + ruff format --check pass; build emits correctly-named artifacts;
191/191 tests pass; coverage 88.91% (floor 75). No version bump, no tag, no publish.

[ernestprovo23]

Superseded by #45 (integrated into the v1.0.0 release commit).