v0.17.0

What's Changed

• Update toolchain to Elixir 1.20 and OTP 29 by @KTSCode in #30
• Add sev help subcommand aliasing top-level usage by @KTSCode in #31
• Make mix todo --done own the CHANGELOG, idempotent, description-driven by @KTSCode in #32
• Add sev help --agent LLM agent reference by @KTSCode in #33

Full Changelog: v0.16.0...v0.17.0