feat: add copy path button to file viewer

web/src/routes/sessions/file.tsx

@@ -5,6 +5,7 @@ import type { GitCommandResponse } from '@/types/api'
 import { FileIcon } from '@/components/FileIcon'
 import { useAppContext } from '@/lib/app-context'
 import { useAppGoBack } from '@/hooks/useAppGoBack'
+import { usePlatform } from '@/hooks/usePlatform'
 import { queryKeys } from '@/lib/query-keys'
 import { langAlias, useShikiHighlighter } from '@/lib/shiki'
 
@@ -119,8 +120,55 @@ function extractCommandError(result: GitCommandResponse | undefined): string | n
     return result.error ?? result.stderr ?? 'Failed to load diff'
 }
 
+function safeCopyToClipboard(text: string): Promise<void> {
+    if (navigator.clipboard?.writeText) {
+        return navigator.clipboard.writeText(text)
+    }
+    return Promise.reject(new Error('Clipboard API not available'))
+}
+
+function CopyIcon(props: { className?: string }) {
+    return (
+        <svg
+            xmlns="http://www.w3.org/2000/svg"
+            width="14"
+            height="14"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth="2"
+            strokeLinecap="round"
+            strokeLinejoin="round"
+            className={props.className}
+        >
+            <rect x="9" y="9" width="13" height="13" rx="2" ry="2" />
+            <path d="M5 15H4a2 2 0 0 1-2-2V4a2 2 0 0 1 2-2h9a2 2 0 0 1 2 2v1" />
+        </svg>
+    )
+}
+
+function CheckIcon(props: { className?: string }) {
+    return (
+        <svg
+            xmlns="http://www.w3.org/2000/svg"
+            width="14"
+            height="14"
+            viewBox="0 0 24 24"
+            fill="none"
+            stroke="currentColor"
+            strokeWidth="2"
+            strokeLinecap="round"
+            strokeLinejoin="round"
+            className={props.className}
+        >
+            <polyline points="20 6 9 17 4 12" />
+        </svg>
+    )
+}
+
 export default function FilePage() {
     const { api } = useAppContext()
+    const { haptic } = usePlatform()
     const goBack = useAppGoBack()
     const { sessionId } = useParams({ from: '/sessions/$sessionId/file' })
     const search = useSearch({ from: '/sessions/$sessionId/file' })
@@ -170,6 +218,18 @@ export default function FilePage() {
     const highlighted = useShikiHighlighter(decodedContent, language)
 
     const [displayMode, setDisplayMode] = useState<'diff' | 'file'>('diff')
+    const [copied, setCopied] = useState(false)
+
+    const handleCopyPath = async () => {
+        try {
+            await safeCopyToClipboard(filePath)
+            haptic.notification('success')
+            setCopied(true)
+            setTimeout(() => setCopied(false), 1500)
+        } catch {
+            haptic.notification('error')
+        }
+    }
 
     useEffect(() => {
         if (diffSuccess && !diffContent) {
@@ -209,7 +269,15 @@ export default function FilePage() {
             <div className="bg-[var(--app-bg)]">
                 <div className="mx-auto w-full max-w-content px-3 py-2 flex items-center gap-2 border-b border-[var(--app-divider)]">
                     <FileIcon fileName={fileName} size={20} />
-                    <span className="text-xs text-[var(--app-hint)]">{filePath}</span>
+                    <span className="min-w-0 flex-1 truncate text-xs text-[var(--app-hint)]">{filePath}</span>
+                    <button
+                        type="button"
+                        onClick={handleCopyPath}
+                        className="shrink-0 rounded p-1 text-[var(--app-hint)] hover:bg-[var(--app-subtle-bg)] hover:text-[var(--app-fg)] transition-colors"
+                        title="Copy path"
+                    >
+                        {copied ? <CheckIcon /> : <CopyIcon />}
+                    </button>
                 </div>
             </div>