feat(agents): add Cursor support to init-agents and init-skills

[John Hill (unlikelyzero)]

I recently joined a team that uses Cursor almost exclusively, and hit this gap firsthand — init-agents had no Cursor target, so this closes that.

Summary

• Add a CursorGenerator that reuses the canonical planner/generator/healer agent specs to produce native Cursor subagents under .cursor/agents
• Merge the Playwright Test MCP server into .cursor/mcp.json, preserving any existing entries
• Write reusable commands to .cursor/commands when --prompts is passed
• Add cursor as an init-skills loop and playwright-cli install --skills target, installing into .cursor/skills

Compatibility note

Cursor's native subagents currently inherit whatever MCP tools are available to the parent agent rather than supporting a documented per-agent tool allowlist. No unsupported tools: frontmatter is generated as a result; this is documented in the Test Agents guide.

Fixes #41563

[Pavel Feldman (pavelfeldman)]

Does cursor not support agents/skills?

[John Hill (unlikelyzero)]

Pavel Feldman (@pavelfeldman)

Yes, actually — Cursor added native support for both in 2.4:

• Subagents: .cursor/agents/*.md, https://cursor.com/docs/subagents
• Skills: .cursor/skills/ (SKILL.md), part of the open Agent Skills standard Anthropic published in late 2025, shared with Claude Code/Codex/Gemini CLI: https://cursor.com/docs/skills

This PR generates into those native locations. I manually verified .cursor/agents + the merged .cursor/mcp.json get picked up correctly in Cursor (planner/generator/healer all discoverable, MCP server connects).

One nuance: Cursor also reads .claude/agents/ and .claude/skills/ directly for compatibility, so in principle the existing Claude output would partially work in Cursor too — but generating true Cursor-native files lets us set Cursor-specific frontmatter (model: inherit) correctly rather than relying on that compatibility shim, matching how this codebase treats every other provider.

[Pavel Feldman (pavelfeldman)]

The history of the topic is that we first supported it for .claude/, and then community aligned on .agents/. We can't ignore / regress claude, but we'd like to see the rest aligned around .agents/. I hope cursor will read frontmatter off any files, regardless of where they are. So to me things already work, what do I miss?