docs: add docs

Author: kenjis

user_guide_src/source/changelogs/v4.4.0.rst

@@ -74,6 +74,7 @@ Message Changes
 Changes
 *******
 
+- **Config:** The deprecated Cookie items in **app/Config/App.php** has been removed.
 - **DownloadResponse:** When generating response headers, does not replace the ``Content-Disposition`` header if it was previously specified.
 
 Deprecations

user_guide_src/source/installation/upgrade_440.rst

@@ -0,0 +1,63 @@
+##############################
+Upgrading from 4.3.x to 4.4.0
+##############################
+
+Please refer to the upgrade instructions corresponding to your installation method.
+
+- :ref:`Composer Installation App Starter Upgrading <app-starter-upgrading>`
+- :ref:`Composer Installation Adding CodeIgniter4 to an Existing Project Upgrading <adding-codeigniter4-upgrading>`
+- :ref:`Manual Installation Upgrading <installing-manual-upgrading>`
+
+.. contents::
+    :local:
+    :depth: 2
+
+Breaking Changes
+****************
+
+Mandatory File Changes
+**********************
+
+Config Files
+============
+
+app/Config/Cookie.php
+---------------------
+
+The Cookie config items in **app/Config/App.php** are no longer used.
+
+1. Copy **app/Config/Cookie.php** from the new framework to your **app/Config**
+   directory, and configure it.
+2. Remove the properties (from ``$cookiePrefix`` to ``$cookieSameSite``) in
+   **app/Config/App.php**.
+
+Breaking Enhancements
+*********************
+
+Project Files
+*************
+
+Some files in the **project space** (root, app, public, writable) received updates. Due to
+these files being outside of the **system** scope they will not be changed without your intervention.
+
+There are some third-party CodeIgniter modules available to assist with merging changes to
+the project space: `Explore on Packagist <https://packagist.org/explore/?query=codeigniter4%20updates>`_.
+
+Content Changes
+===============
+
+The following files received significant changes (including deprecations or visual adjustments)
+and it is recommended that you merge the updated versions with your application:
+
+Config
+------
+
+- @TODO
+
+All Changes
+===========
+
+This is a list of all files in the **project space** that received changes;
+many will be simple comments or formatting that have no effect on the runtime:
+
+- @TODO

user_guide_src/source/installation/upgrading.rst

@@ -16,6 +16,7 @@ See also :doc:`./backward_compatibility_notes`.
 
     backward_compatibility_notes
 
+    upgrade_440
     upgrade_432
     upgrade_431
     upgrade_430