`Cursor` adds PR review, parallel plan execution, and split PR workflows

Code review and execution are getting compressed into one loop. Cursor is moving past autocomplete toward workflow orchestration, and this release looks immediately useful for faster shipping.

• —The release bundles a new PR review flow with faster plan execution, tying review and implementation closer together.
• —Parallel agents are positioned as the speed lever for plans; multi-step work should finish in less wall-clock time.
• —Quick-action pills target common workflows, which cuts prompt friction on repetitive IDE actions.
• —Split PRs in the title suggests smaller, cleaner change sets are becoming a first-class workflow inside Cursor.