[opencode-agent]

Added multi-agent support via coding_agents variable:

• cookiecutter.json:15 new coding_agents option (comma-separated claude,gemini,opencode,pi,copilot or all/none) + __prompts__ with human-readable prompts; defaults to all.
• Template files (all under {{ cookiecutter.project_slug }}/):
  • AGENTS.md:1 – canonical single-source instructions (shared by all agents, read by OpenCode/Pi/Codex/Cursor)
  • CLAUDE.md:1 – @AGENTS.md bridge for Claude Code
  • GEMINI.md:1 – @AGENTS.md bridge for Gemini CLI
  • opencode.json:1 – {"$schema":"https://opencode.ai/config.json","instructions":["AGENTS.md",...]}
  • .claude/settings.local.json, .gemini/settings.json (contextFileName: AGENTS.md), .pi/settings.json, .github/copilot-instructions.md (→ AGENTS.md)
• hooks/post_gen_project.py:98 parse_coding_agents() handles string/comma/list/all/none; :187 selects agents, removes unselected files/dirs (e.g., claude keeps CLAUDE.md+.claude+AGENTS.md, opencode keeps opencode.json+AGENTS.md, none removes all).
• Docs: {{ cookiecutter.project_slug }}/README.md:172 and README.md:12 document usage (coding_agents=all, claude,opencode, none) and file mapping; verified via python3 -m pytest tests/test_cookiecutter.py (14 passed) and manual cookiecutter generations for all/none/claude/gemini/opencode/pi/claude,opencode (correct file presence).

Closes #16

opencode session  |  github run