feat(skills): add bundled opencode autonomous-agent skill
Cherry-picked from PR #880 by @arceus77-7, rebased onto current main with corrections.
Adds opencode skill under skills/autonomous-ai-agents/ with:
- One-shot opencode run workflow
- Interactive/background TUI session workflow
- PR review workflow (including opencode pr command)
- Parallel work patterns
- TUI keybindings reference
- Session/cost management
- Smoke verification
Tested with OpenCode v1.2.25. Fixed /exit bug (not a valid command),
added missing flags (--file, --thinking, --variant), expanded docs.
Co-authored-by: arceus77-7 <261276524+arceus77-7@users.noreply.github.com>
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