fix: use backslashes for Windows paths

lua/frecency/fs.lua

@@ -28,8 +28,8 @@ FS.new = function(config)
     return "^" .. regex .. "$"
   end, self.config.ignore_patterns)
   ---This is needed for Neovim v0.9.0.
-  self.joinpath = vim.fs.joinpath or function(...)
-    return (table.concat({ ... }, "/"):gsub("//+", "/"))
+  self.joinpath = function(...)
+    return Path:new(...).filename
   end
   return self
 end
@@ -56,9 +56,10 @@ function FS:scan_dir(path)
         end,
       })
     do
-      local fullpath = self.joinpath(path, name)
+      local escaped = Path.path.sep ~= "/" and name:gsub("/", Path.path.sep) or name
+      local fullpath = self.joinpath(path, escaped)
       if type == "file" and not self:is_ignored(fullpath) and gitignore({ path }, fullpath) then
-        coroutine.yield(name)
+        coroutine.yield(escaped)
       end
     end
   end)

lua/frecency/picker.lua

@@ -161,11 +161,12 @@ end
 ---@return string
 function Picker:default_path_display(opts, path)
   local filename = Path:new(path):make_relative(opts.cwd)
+  log.debug { cwd = opts.cwd, before = path, after = filename }
   if not self.workspace then
     if vim.startswith(filename, self.fs.os_homedir) then
-      filename = "~/" .. self.fs:relative_from_home(filename)
+      filename = "~" .. Path.path.sep .. self.fs:relative_from_home(filename)
     elseif filename ~= path then
-      filename = "./" .. filename
+      filename = "." .. Path.path.sep .. filename
     end
   end
   return filename