Quorum v0.4.1

What's Changed

• Add Apple-style animated product showcase demo by @alchaplinsky in #145
• Reframe demo narrative as agentic IDE; restructure new-agent screen by @alchaplinsky in #146
• Add @ file-mention autocomplete to the composer by @alchaplinsky in #147
• Add # PR mentions; unify autocompletions on a shared engine by @alchaplinsky in #148

Full Changelog: v0.4.0...v0.4.1