refactor(viz-platform): extract skills and slim commands

Extract shared knowledge from 10 commands into 7 reusable skills:
- mcp-tools-reference.md: All viz-platform MCP tool signatures
- theming-system.md: Theme tokens, CSS variables, color palettes
- accessibility-rules.md: WCAG contrast, color-blind safe palettes
- dmc-components.md: DMC categories, validation, common props
- responsive-design.md: Breakpoints, mobile-first, grid config
- chart-types.md: Plotly chart types, export formats, resolution
- layout-templates.md: Dashboard templates, filter types

All commands now reference skills via "Skills to Load" section.
Commands reduced from 1396 lines total to 427 lines (69% reduction).

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugins/viz-platform/commands/theme-css.md

@@ -4,19 +4,19 @@ description: Export a theme as CSS custom properties
 
 # Export Theme as CSS
 
+## Skills to Load
+- skills/mcp-tools-reference.md
+- skills/theming-system.md
+
 ## Visual Output
 
-When executing this command, display the plugin header:
-
 ```
-┌──────────────────────────────────────────────────────────────────┐
-│  🎨 VIZ-PLATFORM · Theme CSS Export                               │
-└──────────────────────────────────────────────────────────────────┘
++------------------------------------------------------------------+
+|  VIZ-PLATFORM - Theme CSS Export                                 |
++------------------------------------------------------------------+
 ```
 
-Then proceed with the export.
-
-Export a theme's design tokens as CSS custom properties for use outside Dash.
+Export a theme's design tokens as CSS custom properties.
 
 ## Usage
 
@@ -28,94 +28,13 @@ Export a theme's design tokens as CSS custom properties for use outside Dash.
 
 - `name` (required): Theme name to export
 
-## Examples
-
-```
-/theme-css dark
-/theme-css corporate
-/theme-css my-brand
-```
-
 ## Tool Mapping
 
-This command uses the `theme_export_css` MCP tool:
-
 ```python
 theme_export_css(theme_name="corporate")
 ```
 
-## Output Example
-
-```css
-:root {
-  /* Colors */
-  --mantine-color-scheme: light;
-  --mantine-primary-color: indigo;
-  --mantine-color-primary-0: #edf2ff;
-  --mantine-color-primary-1: #dbe4ff;
-  --mantine-color-primary-2: #bac8ff;
-  --mantine-color-primary-3: #91a7ff;
-  --mantine-color-primary-4: #748ffc;
-  --mantine-color-primary-5: #5c7cfa;
-  --mantine-color-primary-6: #4c6ef5;
-  --mantine-color-primary-7: #4263eb;
-  --mantine-color-primary-8: #3b5bdb;
-  --mantine-color-primary-9: #364fc7;
-
-  /* Typography */
-  --mantine-font-family: Inter, sans-serif;
-  --mantine-heading-font-family: Inter, sans-serif;
-  --mantine-font-size-xs: 0.75rem;
-  --mantine-font-size-sm: 0.875rem;
-  --mantine-font-size-md: 1rem;
-  --mantine-font-size-lg: 1.125rem;
-  --mantine-font-size-xl: 1.25rem;
-
-  /* Spacing */
-  --mantine-spacing-xs: 0.625rem;
-  --mantine-spacing-sm: 0.75rem;
-  --mantine-spacing-md: 1rem;
-  --mantine-spacing-lg: 1.25rem;
-  --mantine-spacing-xl: 2rem;
-
-  /* Border Radius */
-  --mantine-radius-xs: 0.125rem;
-  --mantine-radius-sm: 0.25rem;
-  --mantine-radius-md: 0.5rem;
-  --mantine-radius-lg: 1rem;
-  --mantine-radius-xl: 2rem;
-
-  /* Shadows */
-  --mantine-shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.05);
-  --mantine-shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
-  --mantine-shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
-  --mantine-shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
-  --mantine-shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1);
-}
-```
-
-## Use Cases
-
-### External CSS Files
-Include the exported CSS in non-Dash projects:
-```html
-<link rel="stylesheet" href="theme-tokens.css">
-```
-
-### Design Handoff
-Share design tokens with designers or other teams.
-
-### Documentation
-Generate theme documentation for style guides.
-
-### Other Frameworks
-Use Mantine-compatible tokens in React, Vue, or other projects.
-
-## Workflow
-
-1. **User invokes**: `/theme-css corporate`
-2. **Tool exports**: Theme tokens as CSS
-3. **User can**: Save to file or copy to clipboard
+Use cases: external CSS, design handoff, documentation, other frameworks.
 
 ## Related Commands