fix(worktrees): use full paths for bundled scripts

Users were confused by ./scripts/ references, thinking they needed to copy
scripts into their project. Scripts are in ~/.claude/skills/worktrees/scripts/
and should be referenced with full paths.

Changes:
- Updated spawn-issues to use full script paths
- Updated worktrees skill with full paths in all examples
- Fixed gitea model name to claude-haiku-4-5
- Added tools list to issue-worker agent

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

agents/issue-worker/AGENT.md

@@ -5,6 +5,7 @@ description: >
   implementation, commits, pushes, and creates PR. Use when implementing an
   issue as part of parallel workflow.
 model: claude-sonnet-4-5
+tools: Bash, Read, Write, Edit, Glob, Grep, TodoWrite
 skills: gitea, issue-writing, worktrees
 ---