feat: add ui_design_specialist (Phase 3 UI Design) v0.2.0

- New specialist: ui_design_specialist with iterative mockup dialog
- New Phase 3 (UI Design) between Architecture and Implementation
- Relay model: orchestrator passes responses verbatim in Phase 3
- Cost-control exception for UI Design phase (unlimited subagent calls)
- Webspace mockup workflow with cache-buster and obscure dirs
- UX states coverage (loading, empty, error, partial)
- WCAG 2.1 AA accessibility guidelines
- Design tokens (CSS custom properties) in design system
- Component states (hover, focus, active, disabled, loading, error)
- Sitemap/wireframe before mockups for complex UIs
- Real content strategy (no Lorem Ipsum)
- Form validation UX in mockups
- Dark mode and i18n support (optional)
- Design handoff support (specialist available during implementation)
- Skip mechanism for non-UI projects
- Mockup state file for context compression recovery
- Multi-page mockup strategy with index.html
- task_graph.json mockup references
- Plugin version: 0.1.14 -> 0.2.0
- 47 files changed across 7 implementation blocks
- 3 review rounds with 41 corrections integrated

prompts/agent.system.tool.quality_gate.md

@@ -9,3 +9,4 @@ Use this exact Agent Zero tool-call shape:
 Rules:
 - Do not use this tool to discover, read, infer, validate, or print credential values.
 - If the tool is not found, stop and report a runtime tool-registration failure. Do not switch to WebUI login, CSRF, HTTP cache-refresh, shell credential scans, or `.env`/config/log searches.
+- Note: UI Design phase (Phase 3) quality review is handled by `quality_reviewer` subagent, not the `quality_gate` tool. The quality_gate tool covers implementation, runtime, deployment, and release gates. For UI Design gate checks (mockup URLs, UX states, accessibility, design tokens), delegate to `quality_reviewer`.