Add dependency management to issue workflows

Updated skills and commands to identify and formally link issue
dependencies using tea CLI:

Skills updated:
- issue-writing: Document deps in description + link with tea CLI
- backlog-grooming: Check for formal dependency links in checklist
- roadmap-planning: Link dependencies after creating issues

Commands updated:
- create-issue: Ask about and link dependencies for new issues
- plan-issues: Create in dependency order, link with tea issues deps add
- groom: Check dependency status, suggest missing links

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

skills/backlog-grooming/SKILL.md

@@ -33,10 +33,18 @@ For each issue, verify:
 - [ ] Clear boundaries (what's included/excluded)
 
 ### 5. Dependencies
-- [ ] Dependencies identified
+- [ ] Dependencies identified in description
+- [ ] Dependencies formally linked (`tea issues deps list <number>`)
 - [ ] No circular dependencies
 - [ ] Blocking issues are tracked
 
+To check/fix dependencies:
+```bash
+tea issues deps list <number>           # View current dependencies
+tea issues deps add <issue> <blocker>   # Add missing dependency
+tea issues deps remove <issue> <dep>    # Remove incorrect dependency
+```
+
 ### 6. Labels
 - [ ] Type label (bug/feature/etc)
 - [ ] Priority if applicable