fix(rtk/find): detect and group Windows backslash-style find output (#2448)

isPathLike rejected any line with a colon, so Windows absolute paths
(C:\Users\me\a.js) were never recognized and find dumps went uncompacted.
find.js also split only on "/", mis-grouping backslash paths.

- autodetect: treat drive-letter prefix (X:\ or X:/) as path-like before
  the general colon rejection.
- find.js: split on the last "/" or "\" separator and normalize emitted
  directory labels to forward slashes.

Co-authored-by: Cursor <cursoragent@cursor.com>

open-sse/rtk/filters/find.js

@@ -9,16 +9,17 @@ export function find(input) {
   const byDir = new Map();
 
   for (const path of lines) {
-    const lastSlash = path.lastIndexOf("/");
+    // Accept both Unix ("/a/b") and Windows ("C:\a\b") separators
+    const lastSep = Math.max(path.lastIndexOf("/"), path.lastIndexOf("\\"));
     let dir;
     let basename;
-    if (lastSlash === -1) {
+    if (lastSep === -1) {
       dir = ".";
       basename = path;
     } else {
       // Rust: PathBuf::from(path).parent().display() + file_name().display()
-      dir = path.slice(0, lastSlash) || "/";
-      basename = path.slice(lastSlash + 1);
+      dir = path.slice(0, lastSep) || "/";
+      basename = path.slice(lastSep + 1);
     }
     if (!byDir.has(dir)) byDir.set(dir, []);
     byDir.get(dir).push(basename);
@@ -31,7 +32,8 @@ export function find(input) {
   const showDirs = dirs.slice(0, FIND_TOTAL_DIR_MAX);
   for (const dir of showDirs) {
     const files = byDir.get(dir);
-    out += `${dir}/  (${files.length})\n`;
+    const dirLabel = dir.replace(/\\/g, "/");
+    out += `${dirLabel}/  (${files.length})\n`;
     const showFiles = files.slice(0, FIND_PER_DIR_MAX);
     for (const f of showFiles) out += `  ${f}\n`;
     if (files.length > FIND_PER_DIR_MAX) {