feat(file_selector): add intergration with nvim-tree.lua (#1987)

Co-authored-by: doodleEsc <cokie@foxmail.com>
Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

lua/avante/extensions/nvim_tree.lua

@@ -0,0 +1,56 @@
+local Api = require("avante.api")
+
+--- @class avante.extensions.nvim_tree
+local M = {}
+
+--- Adds the currently selected file in NvimTree to the selection via Api.add_selected_file.
+-- Notifies the user if not invoked within NvimTree or if errors occur.
+--- @return nil
+function M.add_file()
+  if vim.bo.filetype ~= "NvimTree" then
+    vim.notify("This action can only be used inside NvimTree.", vim.log.levels.WARN)
+    return
+  end
+
+  local ok, nvim_tree_api = pcall(require, "nvim-tree.api")
+  if not ok then
+    vim.notify("nvim-tree needed", vim.log.levels.ERROR)
+    return
+  end
+
+  local success, node = pcall(function() return nvim_tree_api.tree.get_node_under_cursor() end)
+  if not success then
+    vim.notify("Error getting node: " .. tostring(node), vim.log.levels.ERROR)
+    return
+  end
+
+  local filepath = node.absolute_path
+  Api.add_selected_file(filepath)
+end
+
+--- Removes the currently selected file in NvimTree from the selection via Api.remove_selected_file.
+-- Notifies the user if not invoked within NvimTree or if errors occur.
+--- @return nil
+function M.remove_file()
+  if vim.bo.filetype ~= "NvimTree" then
+    vim.notify("This action can only be used inside NvimTree.", vim.log.levels.WARN)
+    return
+  end
+
+  local ok, nvim_tree_api = pcall(require, "nvim-tree.api")
+  if not ok then
+    vim.notify("nvim-tree needed", vim.log.levels.ERROR)
+    return
+  end
+
+  local success, node = pcall(function() return nvim_tree_api.tree.get_node_under_cursor() end)
+  if not success then
+    vim.notify("Error getting node: " .. tostring(node), vim.log.levels.ERROR)
+    return
+  end
+
+  local filepath = node.absolute_path
+  Api.remove_selected_file(filepath)
+end
+
+return M