Create new fast commit task

This task uses the same logic as the commit task (.claude/commands/commit.md) but automatically selects the first suggested commit message without asking for confirmation.

• Generate 3 commit message suggestions following the same format as the commit task
• Automatically use the first suggestion without asking the user
• Immediately run git commit -m with the first message
• All other behaviors remain the same as the commit task (format, package names, staged files only)
• Do NOT add Claude co-authorship footer to commits