fix: polish workspace files and editor shell

frontend/src/lib/ui/Icon.svelte

@@ -1,6 +1,6 @@
 <script>
   /**
-   * Icon.svelte — Renders inline SVG icons.
+   * Icon.svelte — Renders bundled Lucide SVG icons.
    *
    * Usage:
    *   <Icon name="puzzle" size={18} />
@@ -8,26 +8,60 @@
    *
    * Rules:
    *   - NO emoji, NO unicode pictographic symbols
-   *   - ALL icons must be SVG registered in ../ui/icons.js
-   *   - If name is not found, renders a default dot icon
+   *   - NO dependency on system icon fonts
+   *   - If name is not found, renders a default circle icon
    */
-  import { iconPaths } from './icons.js';
+  import Briefcase from 'lucide-svelte/icons/briefcase';
+  import ChevronDown from 'lucide-svelte/icons/chevron-down';
+  import ChevronRight from 'lucide-svelte/icons/chevron-right';
+  import Circle from 'lucide-svelte/icons/circle';
+  import FlaskConical from 'lucide-svelte/icons/flask-conical';
+  import Folder from 'lucide-svelte/icons/folder';
+  import LayoutGrid from 'lucide-svelte/icons/layout-grid';
+  import PanelsTopLeft from 'lucide-svelte/icons/panels-top-left';
+  import Pencil from 'lucide-svelte/icons/pencil';
+  import Plug from 'lucide-svelte/icons/plug';
+  import Puzzle from 'lucide-svelte/icons/puzzle';
+  import Settings from 'lucide-svelte/icons/settings';
+  import Shield from 'lucide-svelte/icons/shield';
+  import TriangleAlert from 'lucide-svelte/icons/triangle-alert';
 
   export let name = 'dot';
   export let size = 16;
   export let className = '';
 
-  $: icon = iconPaths[name] || iconPaths.dot;
+  const icons = {
+    case: Briefcase,
+    chevronDown: ChevronDown,
+    chevronRight: ChevronRight,
+    dot: Circle,
+    edit: Pencil,
+    flask: FlaskConical,
+    folder: Folder,
+    gear: Settings,
+    logo: PanelsTopLeft,
+    plugin: Plug,
+    puzzle: Puzzle,
+    space: LayoutGrid,
+    vault: Shield,
+    warning: TriangleAlert,
+  };
+
+  const aliases = {
+    '🧪': 'flask',
+    danger: 'warning',
+    settings: 'gear',
+  };
+
+  $: iconKey = aliases[name] || name || 'dot';
+  $: IconComponent = icons[iconKey] || icons.dot;
+  $: iconClass = [className, $$restProps.class].filter(Boolean).join(' ');
 </script>
 
-<svg
-  xmlns="http://www.w3.org/2000/svg"
-  viewBox={icon.viewBox}
-  width={size}
-  height={size}
-  class={className}
->
-  {#each icon.paths as p}
-    <path d={p.d} {...p.attrs} />
-  {/each}
-</svg>
+<svelte:component
+  this={IconComponent}
+  size={size}
+  {...$$restProps}
+  class={iconClass}
+  aria-hidden="true"
+/>