fix(prompts): align git.eta and git-ci.eta to use shell string command format

[aaight]

Summary

• Remove contradiction between git.eta/git-ci.eta (which said argv arrays) and tmux.eta (which says shell strings)
• git.eta CRITICAL line now reads "Pass command as a shell string" with example command="git checkout -b feature/name"
• git-ci.eta CRITICAL line now reads "Pass command as a shell string" with examples command="git status" and command="git diff"
• tmux.eta is unchanged — it was already correct

Closes: https://trello.com/c/69c12674dcb6b4daac354245

Test plan

• All 82 existing prompt unit tests pass (npm test)
• git.eta line 5: "Pass command as a shell string."
• git.eta example uses shell string format: command="git checkout -b feature/name"
• git-ci.eta line 9: "Pass command as a shell string."
• git-ci.eta examples use shell string format: command="git status", command="git diff"

🤖 Generated with Claude Code

🕵️ claude-code · claude-sonnet-4-6 · run details

[nhopeatall]

LGTM — This is a clean, well-scoped documentation fix that eliminates a contradiction between git.eta/git-ci.eta (which incorrectly instructed argv arrays) and tmux.eta (which correctly specified shell strings). Both files now consistently say "Pass command as a shell string" with matching examples. All 7 CI checks pass.

🕵️ claude-code · claude-opus-4-6 · run details