fix(web): use compact icon button sizes

Quentin Gliech and Claude Opus 4.6 (1M context) created 

Theme toggle: icon → icon-sm (32px instead of 36px).
FileViewer copy button: icon with size-7 override → icon-xs (24px).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Change summary

webui2/src/components/code/file-viewer.tsx | 3 +--
webui2/src/components/layout/header.tsx    | 2 +-
2 files changed, 2 insertions(+), 3 deletions(-)

Detailed changes

webui2/src/components/code/file-viewer.tsx 🔗 

@@ -245,8 +245,7 @@ export function FileViewer({ blob }: FileViewerProps) {
         </span>
         <Button
           variant="ghost"
-          size="icon"
-          className="size-7"
+          size="icon-xs"
           onClick={copyToClipboard}
           title="Copy"
         >

webui2/src/components/layout/header.tsx 🔗 

@@ -59,7 +59,7 @@ export function Header() {
         <div className="ml-auto flex items-center gap-2">
           {mode === "readonly" && <span className="text-muted-foreground text-xs">Read only</span>}
 
-          <Button variant="ghost" size="icon" onClick={toggle} title="Toggle theme">
+          <Button variant="ghost" size="icon-sm" onClick={toggle} title="Toggle theme">
             {theme === "light" ? <Moon className="size-4" /> : <Sun className="size-4" />}
           </Button>