feat: tool timeout auto-retry, file tree attachment, force stop button

- Add configurable tool timeout with auto-retry: when a tool exceeds the
  timeout threshold, abort and send a follow-up message asking Claude to
  try a different approach
- Add "+" button on file tree items to attach files directly to chat
  input via new /api/files/raw endpoint and custom event bridge
- Add force stop button in streaming status bar when tool runs >90s,
  with warning indicators at 60s
- Improve doc preview markdown rendering (padding, list indentation)
- Bump version to 0.10.0

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

src/components/ai-elements/file-tree.tsx

@@ -13,6 +13,7 @@ import {
   FileIcon,
   FolderIcon,
   FolderOpenIcon,
+  PlusIcon,
 } from "lucide-react";
 import {
   createContext,
@@ -27,6 +28,7 @@ interface FileTreeContextType {
   togglePath: (path: string) => void;
   selectedPath?: string;
   onSelect?: (path: string) => void;
+  onAdd?: (path: string) => void;
 }
 
 // Default noop for context default value
@@ -44,6 +46,7 @@ export type FileTreeProps = HTMLAttributes<HTMLDivElement> & {
   defaultExpanded?: Set<string>;
   selectedPath?: string;
   onSelect?: (path: string) => void;
+  onAdd?: (path: string) => void;
   onExpandedChange?: (expanded: Set<string>) => void;
 };
 
@@ -52,6 +55,7 @@ export const FileTree = ({
   defaultExpanded = new Set(),
   selectedPath,
   onSelect,
+  onAdd,
   onExpandedChange,
   className,
   children,
@@ -75,8 +79,8 @@ export const FileTree = ({
   );
 
   const contextValue = useMemo(
-    () => ({ expandedPaths, onSelect, selectedPath, togglePath }),
-    [expandedPaths, onSelect, selectedPath, togglePath]
+    () => ({ expandedPaths, onAdd, onSelect, selectedPath, togglePath }),
+    [expandedPaths, onAdd, onSelect, selectedPath, togglePath]
   );
 
   return (
@@ -204,7 +208,7 @@ export const FileTreeFile = ({
   children,
   ...props
 }: FileTreeFileProps) => {
-  const { selectedPath, onSelect } = useContext(FileTreeContext);
+  const { selectedPath, onSelect, onAdd } = useContext(FileTreeContext);
   const isSelected = selectedPath === path;
 
   const handleClick = useCallback(() => {
@@ -220,13 +224,21 @@ export const FileTreeFile = ({
     [onSelect, path]
   );
 
+  const handleAdd = useCallback(
+    (e: React.MouseEvent) => {
+      e.stopPropagation();
+      onAdd?.(path);
+    },
+    [onAdd, path]
+  );
+
   const fileContextValue = useMemo(() => ({ name, path }), [name, path]);
 
   return (
     <FileTreeFileContext.Provider value={fileContextValue}>
       <div
         className={cn(
-          "flex cursor-pointer items-center gap-1 rounded px-2 py-1 transition-colors hover:bg-muted/50",
+          "group/file flex cursor-pointer items-center gap-1 rounded px-2 py-1 transition-colors hover:bg-muted/50",
           isSelected && "bg-muted",
           className
         )}
@@ -244,6 +256,16 @@ export const FileTreeFile = ({
               {icon ?? <FileIcon className="size-4 text-muted-foreground" />}
             </FileTreeIcon>
             <FileTreeName>{name}</FileTreeName>
+            {onAdd && (
+              <button
+                type="button"
+                className="ml-auto flex size-5 shrink-0 items-center justify-center rounded opacity-0 transition-opacity hover:bg-muted group-hover/file:opacity-100"
+                onClick={handleAdd}
+                title="Add to chat"
+              >
+                <PlusIcon className="size-3 text-muted-foreground" />
+              </button>
+            )}
           </>
         )}
       </div>