Bridge .claude/CLAUDE.md to GEMINI.md in gemini-cli driver

[moodmosaic]

Summary

Gemini CLI reads GEMINI.md for project instructions, not
.claude/CLAUDE.md. Projects that only provide a CLAUDE.md
(the Claude Code convention) get no project-level guidance
when run through the Gemini CLI driver.

Proposed fix

In gemini-cli.sh agent_settings(), if GEMINI.md does
not exist at the workspace root, check for
.claude/CLAUDE.md (then CLAUDE.md), copy it to
GEMINI.md, and add it to .git/info/exclude.

Mirror the approach used in codex-cli.sh.

Motivation

Most existing swarm configs target Claude Code and store their
project instructions in .claude/CLAUDE.md. When running
these same projects with Gemini agents, the instructions are
silently ignored because Gemini CLI never looks at that path.

The Codex CLI driver already bridges this gap (copies
.claude/CLAUDE.md to AGENTS.md in agent_settings).
The Gemini driver should do the equivalent for GEMINI.md.