ci: build versioned installers across desktop platforms

Merge pull request #3 from Zns-Nexus/docs/project-agents

Merge pull request #1 from Zns-Nexus/feat/macos-version

Build without implicit publishing and use current runner actions

Point the install section at the public releases page

Add the release lane: a GitHub Actions workflow and a local release script

Bump to 0.1.2 for the logo, veil and MCP dropdown release

Aggregate Mail: a keyboard-driven desktop inbox for every account