fix: confirm ui (#1665)

lua/avante/ui/line.lua

@@ -0,0 +1,38 @@
+---@alias avante.ui.LineSection string[]
+---
+---@class avante.ui.Line
+---@field sections avante.ui.LineSection[]
+local M = {}
+M.__index = M
+
+---@param sections avante.ui.LineSection[]
+function M:new(sections)
+  local this = setmetatable({}, M)
+  this.sections = sections
+  return this
+end
+
+---@param ns_id number
+---@param bufnr number
+---@param line number
+function M:set_highlights(ns_id, bufnr, line)
+  if not vim.api.nvim_buf_is_valid(bufnr) then return end
+  local col_start = 0
+  for _, section in ipairs(self.sections) do
+    local text = section[1]
+    local highlight = section[2]
+    if highlight then vim.api.nvim_buf_add_highlight(bufnr, ns_id, highlight, line, col_start, col_start + #text) end
+    col_start = col_start + #text
+  end
+end
+
+function M:__tostring()
+  local content = {}
+  for _, section in ipairs(self.sections) do
+    local text = section[1]
+    table.insert(content, text)
+  end
+  return table.concat(content, "")
+end
+
+return M