feat(cli): add Gemini CLI as a per-tool build target

[tkman59]

Problem to solve

aidd-cli adapts an archive per supported tool at release time. Today the release assets cover Claude Code (native), GitHub Copilot, Codex, Cursor and OpenCode.

Gemini CLI is missing. Users on Gemini CLI have no supported path to the AIDD SDLC: they either copy skills by hand into GEMINI.md — losing per-skill routing and the update flow — or they don't use the framework at all.

Proposed solution

Add gemini as a build target, producing a flat archive (aidd-framework-gemini-flat-.zip) that materializes into the project, same shape as the existing Cursor and OpenCode flat targets.

Marketplace format is out of scope: Gemini CLI has no plugin-manager equivalent to aidd marketplace add.

Content type

• Rule
• Skill
• Command
• Agent
• Plugin
• Other

Target tool(s)

• Claude Code
• Cursor
• Windsurf
• Gemini CLI
• Other

Additional context

Surface mapping (to be confirmed against Gemini CLI docs)

AIDD surface	Claude Code	Proposed Gemini CLI target
Rules / context	CLAUDE.md	GEMINI.md (Gemini CLI also reads AGENTS.md)
Skills	plugins/ /skills//SKILL.md	SKILL.md, possibly unchanged — see below
MCP servers	.mcp.json	mcpServers in .gemini/settings.json
Agents	plugins/ /agents/*.md	⚠️ needs investigation — no known equivalent
Hooks	hooks/hooks.json (Node)	⚠️ needs investigation

Code of Conduct

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