Load Gemini tool mapping via GEMINI.md @import instead of skill reference

The tool mapping table is now @referenced directly in GEMINI.md so Gemini
CLI always has it in context when processing skills, rather than requiring
Gemini to find and read a reference file from within the skill.

GEMINI.md

@@ -1 +1,2 @@
 @./skills/using-superpowers/SKILL.md
+@./skills/using-superpowers/references/gemini-tools.md

skills/using-superpowers/SKILL.md

@@ -35,7 +35,7 @@ If CLAUDE.md, GEMINI.md, or AGENTS.md says "don't use TDD" and a skill says "alw
 
 ## Platform Adaptation
 
-Skills use Claude Code tool names. Non-CC platforms: see `references/codex-tools.md` (Codex) or `references/gemini-tools.md` (Gemini CLI) for tool equivalents.
+Skills use Claude Code tool names. Non-CC platforms: see `references/codex-tools.md` (Codex) for tool equivalents. Gemini CLI users get the tool mapping loaded automatically via GEMINI.md.
 
 # Using Skills