I've successfully renamed the "Spinoff Task" button to "Create Subtask". Here's what was changed:
### Changes Made
**File:** `frontend/src/components/tasks/Toolbar/CurrentAttempt.tsx`
- **Line 137**: Renamed `handleSpinoffClick` → `handleCreateSubtaskClick`
- **Line 710**: Updated click handler reference
- **Line 716**: Changed button text from "Spinoff Task" → "Create Subtask"
### Validation Results
✅ **Rust clippy**: Passed with no warnings
✅ **Code formatting**: All files properly formatted
✅ **Frontend linting**: Passed with 98 warnings (no errors)
The button now uses the more intuitive "Create Subtask" label, which better communicates its purpose of creating a hierarchical child task linked to the current task attempt.
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