Add config to limit max height for selected files (#2618)

lua/avante/config.lua

@@ -627,6 +627,9 @@ M._defaults = {
       prefix = "> ",
       height = 8, -- Height of the input window in vertical layout
     },
+    selected_files = {
+      height = 6, -- Maximum height of the selected files window
+    },
     edit = {
       border = { " ", " ", " ", " ", " ", " ", " ", " " },
       start_insert = true, -- Start insert mode when opening the edit window

lua/avante/sidebar.lua

@@ -2963,7 +2963,7 @@ end
 
 function Sidebar:get_selected_files_container_height()
   local selected_filepaths_ = self.file_selector:get_selected_filepaths()
-  return math.min(vim.o.lines - 2, #selected_filepaths_ + 1)
+  return math.min(Config.windows.selected_files.height, #selected_filepaths_ + 1)
 end
 
 function Sidebar:adjust_selected_files_container_layout()