Create researcher-workflow skill

## Task Create a new "researcher-workflow" skill for the skills system. ## Context We have other workflow skills like `worker-workflow`, `review-workflow`, `orchestrator-workflow`, and `git-workflow`. We need a similar skill for the researcher agent. ## Requirements The researcher-workflow skill should: 1. **Guide researchers** on how to work effectively within the Tinker system 2. **Cover researcher responsibilities**: - Analyzing tickets, memories, and comments - Generating proposals for new work - Identifying patterns and improvements - Marking items as reviewed - Memory consolidation tasks 3. **Follow the same pattern** as other workflow skills: - Provide guidance on HOW to work - Cover task execution best practices - Explain decision escalation when needed - Document team coordination ## Notes - Reference existing workflow skills for structure and tone - The researcher is a background agent that proactively maintains memory hygiene and generates proposals - Look at `worker-workflow` skill as a template for format and style