0.4.0-rc

What's Changed

• chore: Rename master to main in license by @ivov in #8
• docs: Add release instructions by @ivov in #9
• ci: Introduce linting by @ivov in #10
• feat: Handshake with main by @ivov in #6
• refactor: Rename Go module to align with repository name by @ivov in #12
• ci: Add notify PR status workflow by @tomi in #14
• feat: Launch runner on demand by @ivov in #13
• refactor: Introduce log levels by @ivov in #11
• feat: Add health check endpoint by @ivov in #15
• feat: Ensure main instance is ready on startup and available on token exchange by @ivov in #16
• refactor: Set up env config by @ivov in #17
• refactor: Improve naming by @ivov in #19
• docs: Add security notice by @ivov in #20
• test: Set up tests and add coverage for env package by @ivov in #21
• feat: Monitor runner health by @ivov in #18
• feat: Set sane defaults for all URIs by @ivov in #22

Full Changelog: 0.3.0-rc...0.4.0-rc