feat(ui): syntax-highlight the read-only source previews (#1284)

The read-only previews beside Problems, Show Usages and TODO results are syntax-coloured from one whole-file parse (capped for very large files), so a line inside a block comment or a multi-line string is coloured as such; the pane renders plain first and recolours when the parse lands. SourcePreview takes the colouring as a colorize prop (the editor's previewColors), keeping src/ui free of editor imports, and the tok-* colours live once in global.css instead of a copy per view, with the theme's comment style.

Co-authored-by: qtvbwfn <[email protected]>

src/features/code-insight/ProblemsView.tsx

@@ -4,6 +4,7 @@ import { create } from "zustand";
 import clsx from "clsx";
 import type { Diagnostic, Severity } from "@/bindings";
 import { useEditorRegistry } from "@/editor/api";
+import { previewColors } from "@/editor/lineTokens";
 import { executeAction } from "@/platform/actions";
 import { formatBinding, hasPrimaryModifier, hostBinding, shortcutLabel } from "@/platform/keymap";
 import { basename, relativeDir, useProject } from "@/platform/project";
@@ -409,6 +410,7 @@ export function ProblemsView() {
                 line={selected?.d.range.start.line ?? 0}
                 highlights={selected ? [diagHighlight(selected.d)] : []}
                 load={previewText}
+                colorize={previewColors}
               />
             </SplitPanel>
           </SplitGroup>