feat: add Windows support for git directory scanning (#1391)

lua/avante/utils/init.lua

@@ -715,6 +715,18 @@ function M.scan_directory(options)
   if not cmd then
     local p = Path:new(options.directory)
     if p:joinpath(".git"):exists() and vim.fn.executable("git") == 1 then
+      if vim.fn.has("win32") == 1 then
+        cmd = {
+          "powershell",
+          "-NoProfile",
+          "-NonInteractive",
+          "-Command",
+          string.format(
+            "Push-Location '%s'; (git ls-files --exclude-standard), (git ls-files --exclude-standard --others)",
+            options.directory:gsub("/", "\\")
+          ),
+        }
+      else
         cmd = {
           "bash",
           "-c",
@@ -723,6 +735,7 @@ function M.scan_directory(options)
             options.directory
           ),
         }
+      end
       cmd_supports_max_depth = false
     else
       M.error("No search command found")