add-platform

Add support for a new AI coding tool, IDE, PR-reviewer, or context-packer to VibeTags — wire a new generated output file through ServiceRegistry, Platform, the renderer registry, and (if granular) GranularRulesWriter. Use when the user says "add platform support", "support <tool>", "generate a new output file for X", "new AI platform", or names an AI coding assistant/IDE/PR-reviewer/context-packer VibeTags doesn't…