[thebrandonlucas]

Sets the crate version to 0.2.0 and moves the Unreleased changelog entries into a 0.2.0 - 2026-10-22 section. This is needed before a v0.2.0 tag can pass the release workflow's verify job, which requires the tag to match Cargo.toml.

0.2.0 is a minor bump, not a patch, because this release breaks existing behaviour. Commands that change something now only describe the change (exit 6) unless --execute or VOLTAGE_EXECUTE=1 is given. A new summary line at the top of the 0.2.0 section calls this out.

File	Change
Cargo.toml, Cargo.lock	0.1.0 → 0.2.0
CHANGELOG.md	New empty Unreleased section. Existing entries now sit under ## 0.2.0 - 2026-10-22 with a summary line.

After merge

1. git tag v0.2.0 <merge commit> && git push origin v0.2.0. The release workflow then builds, attests and signs the archives, and opens a draft release.
2. Run staging acceptance and record its results.
3. Publish the draft.

Checks

• Verification gate (nix develop): cargo fmt --check, cargo clippy --locked --all-targets -- -D warnings, cargo machete --with-metadata, cargo test --locked (all pass), and python3 scripts/check-coverage.py.
• voltage --version reports voltage 0.2.0.
• CRAP report: not run. The change does not touch src/ or tests/.
• Review: the diff is version metadata and changelog only. It has no new error paths to test.

Limits

• docs/development.md says to record staging acceptance results "in the validation baseline below", but that section does not exist. This PR does not add it.