feat: redesign Manage tab to match reference layout

- Add Customization group: User Interface (CUI), Tool Palettes (large),
  Import, Export, Edit Aliases dropdown (small)
- Add Cleanup group: Find Non-Purgeable Items (large), Purge, Overkill, Audit (small)
- Add 8 new SVG icons for all new commands

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/modules/manage/options.rs

@@ -1,4 +1,5 @@
 use crate::modules::{IconKind, ModuleEvent, ToolDef};
+#[allow(dead_code)]
 pub fn tool() -> ToolDef {
     ToolDef {
         id: "OPTIONS",