feat(dyl-stack): add dyl-stack plugin

[dgattey]

Summary

• Adds dyl-stack: Dylan's agent style layered on pstack (dyl-mode router + dyl-agent), plus build-figma (Figma → repo design system with a visual judge), dyl-review (paste-ready PR reviews), dyl-ready-pr (review → babysit to green), and principle-the-algorithm.
• No bundled copies of other plugins. It requires pstack and cursor-team-kit, and thermos and figma where a skill needs them. If one is missing, the skill stops and says to run /add-plugin <name>. There are no silent fallbacks.
• Registers it in marketplace.json and the root README.

Test plan

• node scripts/validate-plugins.mjs passes
• Headless agent -p runs with dyl-stack installed locally:
  • /dyl-mode without cursor-team-kit stops with the add-plugin hint
  • /dyl-mode with everything installed reaches pstack's poteto-mode via the setup-pstack anchor and runs the bug-fix playbook
  • /build-figma stops at missing cursor-team-kit and at an unauthenticated Figma MCP
  • /dyl-review deep stops at missing thermos
• Case with pstack absent (needs pstack disabled; not tested)

Made with Cursor

[cursor]

Cursor Bugbot has reviewed your changes using high effort and found 2 potential issues.

^{Bugbot Autofix is ON, but it could not run because the branch was deleted or merged before autofix could start.}

^{Reviewed by Cursor Bugbot for commit a5064ff. Configure here.}