v1.0.2

Added

• Slash command /c4-model via commands/c4-model.md. Lets users invoke the skill explicitly instead of relying only on description-triggered activation. The command routes to the right mode based on what follows the invocation (idea, repo path, pasted diagram, prose document), or asks the user to pick if nothing follows. Registered in marketplace.json via a new commands: ["./commands"] entry.