feat(adapters): add gemini-cli runtime adapter

[HongmingWang-Rabbit]

Summary

• Adds gemini-cli as a new workspace runtime adapter backed by Google Gemini CLI (~101k ⭐, Apache 2.0, v0.38.1)
• Mirrors the claude-code adapter pattern: Dockerfile installs @google/gemini-cli globally, CLIAgentExecutor drives the subprocess, A2A MCP tools wire via ~/.gemini/settings.json (Gemini CLI's native MCP config path)
• Closes feat(adapters): add gemini-cli runtime adapter to workspace-template #332

What changed

File	Change
workspace-template/adapters/gemini_cli/	New adapter — Dockerfile, adapter.py, __init__.py, requirements.txt
workspace-template/cli_executor.py	Adds gemini-cli to RUNTIME_PRESETS; adds mcp_via_settings preset flag to skip --mcp-config injection for runtimes that own their own settings file
workspace-configs-templates/gemini-cli/	Default config.yaml + system-prompt.md
workspace-template/tests/test_adapters.py	Adds gemini-cli to expected adapter registry set
CLAUDE.md	Documents new runtime in image table

Architecture decisions

• Peer adapter, not base-class refactor. Per the scope discussion on feat(adapters): add gemini-cli runtime adapter to workspace-template #332, this is a standalone adapter alongside claude-code, not a shared agentic-cli base class. The shared-base refactor is deferred to when a 3rd agentic-CLI runtime arrives (tracked separately).
• MCP via ~/.gemini/settings.json. Gemini CLI does not accept --mcp-config as a CLI flag — it reads from the user settings file. The adapter's setup() method merges the A2A MCP server into that file, preserving any user-defined MCP tools.
• GEMINI.md as memory file. Gemini CLI reads GEMINI.md from the working directory as persistent context (equivalent of CLAUDE.md for claude-code). setup() seeds it from system-prompt.md on first boot.
• GEMINI_API_KEY required. Must be set as a global secret before provisioning a gemini-cli workspace.

Build

bash workspace-template/build-all.sh gemini-cli

Test plan

• All 1213 pytest tests pass (1213 passed, 2 skipped, 2 xfailed)
• Adapter discovery returns gemini-cli in discover_adapters()
• CLIAgentExecutor command for gemini-cli is ['gemini', '--yolo', '--model', ..., '-p', ...] — no --mcp-config flag
• docker build -t workspace-template:gemini-cli -f workspace-template/adapters/gemini_cli/Dockerfile workspace-template/ succeeds (requires Docker + npm registry access)
• With GEMINI_API_KEY set: workspace boots, delegate_task round-trips, commit_memory/recall_memory work

🤖 Generated with Claude Code