v0.3.0

What's Changed

• build: adopt Task + golangci-lint + gotestsum (v0.3.0 PR 1/10) by @peczenyj in #7
• feat(common): public contracts package (v0.3.0 PR 2/10) by @peczenyj in #8
• feat: internal/sizes + internal/match (v0.3.0 PR 3/10) by @peczenyj in #9
• ci: upload coverage to Codecov by @peczenyj in #11
• feat: internal/testutil + internal/loader (v0.3.0 PR 4/10) by @peczenyj in #10
• refactor: decouple into pkg/common + internal packages (v0.3.0) by @peczenyj in #12
• test+chore: coverage tests + gitignore docs/superpowers (missed by #12 merge) by @peczenyj in #13

Full Changelog: v0.2.0...v0.3.0