refactor(init): merge init logic into setup for simplicity

Simplifies plugin initialization by merging the init logic into the setup
function. Removes the separate init function and ensures all configuration,
provider setup, and chat initialization are handled in setup. This reduces
redundancy and makes the initialization flow clearer.

Signed-off-by: Tomas Slusny <slusnucky@gmail.com>

Author: deathbeam

lua/CopilotChat/init.lua

@@ -28,7 +28,7 @@ local M = setmetatable({}, {
     local initialized = rawget(t, 'initialized')
     if not initialized then
       rawset(t, 'initialized', true)
-      rawget(t, 'init')()
+      rawget(t, 'setup')()
     end
 
     return rawget(t, key)
@@ -1061,8 +1061,20 @@ function M.log_level(level)
   end
 end
 
---- Initialize the plugin if not already initialized.
-function M.init()
+--- Set up the plugin
+---@param config CopilotChat.config.Config?
+function M.setup(config)
+  for k, v in pairs(vim.tbl_deep_extend('force', M.config, config or {})) do
+    M.config[k] = v
+  end
+
+  if not M.config.separator or M.config.separator == '' then
+    log.warn(
+      'Empty separator is not allowed, using default separator instead. Set `separator` in config to change this.'
+    )
+    M.config.separator = '---'
+  end
+
   -- Set log level
   if M.config.debug then
     M.log_level('debug')
@@ -1077,70 +1089,50 @@ function M.init()
   })
 
   -- Load the providers
+  client:stop()
   client:set_providers(function()
     return M.config.providers
   end)
 
   -- Initialize chat
-  if not M.chat then
-    M.chat = require('CopilotChat.ui.chat')(M.config, function(bufnr)
-      for name, _ in pairs(M.config.mappings) do
-        map_key(name, bufnr)
-      end
-
-      require('CopilotChat.completion').enable(bufnr, M.config.chat_autocomplete)
-
-      vim.api.nvim_create_autocmd({ 'BufEnter', 'BufLeave' }, {
-        buffer = bufnr,
-        callback = function(ev)
-          if ev.event == 'BufEnter' then
-            update_source()
-          end
-
-          vim.schedule(function()
-            select.highlight(state.source.bufnr, not (M.config.highlight_selection and M.chat:focused()))
-          end)
-        end,
-      })
+  if M.chat then
+    M.chat:close(state.source.bufnr)
+    M.chat:delete()
+  end
 
-      if M.config.insert_at_end then
-        vim.api.nvim_create_autocmd({ 'InsertEnter' }, {
-          buffer = bufnr,
-          callback = function()
-            vim.cmd('normal! 0')
-            vim.cmd('normal! G$')
-            vim.v.char = 'x'
-          end,
-        })
-      end
+  M.chat = require('CopilotChat.ui.chat')(M.config, function(bufnr)
+    for name, _ in pairs(M.config.mappings) do
+      map_key(name, bufnr)
+    end
 
-      finish(true)
-    end)
-  end
-end
+    require('CopilotChat.completion').enable(bufnr, M.config.chat_autocomplete)
 
---- Set up the plugin
----@param config CopilotChat.config.Config?
-function M.setup(config)
-  for k, v in pairs(vim.tbl_deep_extend('force', M.config, config or {})) do
-    M.config[k] = v
-  end
+    vim.api.nvim_create_autocmd({ 'BufEnter', 'BufLeave' }, {
+      buffer = bufnr,
+      callback = function(ev)
+        if ev.event == 'BufEnter' then
+          update_source()
+        end
 
-  if not M.config.separator or M.config.separator == '' then
-    log.warn(
-      'Empty separator is not allowed, using default separator instead. Set `separator` in config to change this.'
-    )
-    M.config.separator = '---'
-  end
+        vim.schedule(function()
+          select.highlight(state.source.bufnr, not (M.config.highlight_selection and M.chat:focused()))
+        end)
+      end,
+    })
 
-  if M.chat then
-    client:stop()
-    M.chat:close(state.source.bufnr)
-    M.chat:delete()
-    M.chat = nil
-  end
+    if M.config.insert_at_end then
+      vim.api.nvim_create_autocmd({ 'InsertEnter' }, {
+        buffer = bufnr,
+        callback = function()
+          vim.cmd('normal! 0')
+          vim.cmd('normal! G$')
+          vim.v.char = 'x'
+        end,
+      })
+    end
 
-  M.init()
+    finish(true)
+  end)
 
   for name, prompt in pairs(list_prompts()) do
     if prompt.prompt then