feat: support plain icon.svg for plugin icon preview

Author: soderlind

README.md

@@ -229,7 +229,7 @@ Search order (first existing directory wins precedence if duplicates):
 
 Supported file patterns (case-insensitive):
 - Banners: `banner-1544x500.(png|jpg)` (large), `banner-772x250.(png|jpg)` (small)
-- Icons: `icon-256x256.*`, `icon-128x128.*`, `icon-64x64.*`, `icon-32x32.*` (`.png`, `.jpg`, `.jpeg`, `.svg`)
+- Icons: `icon.svg` (scalable, preferred), `icon-256x256.*`, `icon-128x128.*`, `icon-64x64.*`, `icon-32x32.*` (`.png`, `.jpg`, `.jpeg`, `.svg`)
 - Screenshots: `screenshot-1.(png|jpg|jpeg|gif)`, `screenshot-2.*`, etc.
 
 The best available icon size is chosen in order: 256 → 128 → 64 → 32. Screenshots are displayed in ascending numerical order.

src/preview/htmlGenerator.ts

@@ -176,7 +176,8 @@ export class HtmlGenerator {
 
   private pickBestIcon(icons: { [size: string]: vscode.Uri } | undefined): vscode.Uri | undefined {
     if (!icons) return undefined;
-    const preferred = ['256','128','64','32'];
+    // Prefer scalable SVG, then largest raster sizes
+    const preferred = ['svg', '256','128','64','32'];
     for (const p of preferred) {
       if (icons[p]) return icons[p];
     }

src/preview/previewProvider.ts

@@ -421,6 +421,7 @@ ReadmePreviewProvider.prototype.collectPluginAssets = async function(resource: v
   const bannerLargeRegex = /^banner-(?:1544x500|1544x500@2x)\.(png|jpe?g)$/i;
   const bannerSmallRegex = /^banner-(?:772x250|772x250@2x)\.(png|jpe?g)$/i;
   const iconRegex = /^icon-(\d{2,3})x\1\.(png|jpe?g|svg)$/i; // icon-256x256.png
+  const iconSvgRegex = /^icon\.svg$/i; // plain icon.svg (scalable, preferred)
   const screenshotRegex = /^screenshot-(\d+)\.(png|jpe?g|gif)$/i;
 
   for (const dir of assetDirs) {
@@ -434,6 +435,9 @@ ReadmePreviewProvider.prototype.collectPluginAssets = async function(resource: v
         } else if (bannerSmallRegex.test(name)) {
           assets.banner = assets.banner || {};
           assets.banner.small = vscode.Uri.joinPath(dir, name);
+        } else if (iconSvgRegex.test(name)) {
+          // Plain icon.svg (scalable) - store under 'svg' key with highest priority
+          assets.icons!['svg'] = vscode.Uri.joinPath(dir, name);
         } else {
           const iconMatch = name.match(iconRegex);
           if (iconMatch) {