docs: add changelog and upgrading

Author: kenjis

user_guide_src/source/changelogs/index.rst

@@ -12,6 +12,7 @@ See all the changes.
 .. toctree::
     :titlesonly:
 
+    v4.3.3
     v4.3.2
     v4.3.1
     v4.3.0

user_guide_src/source/changelogs/v4.3.3.rst

@@ -0,0 +1,32 @@
+Version 4.3.3
+#################
+
+Release Date: Unreleased
+
+**4.3.3 release of CodeIgniter4**
+
+.. contents::
+    :local:
+    :depth: 3
+
+BREAKING
+********
+
+Message Changes
+***************
+
+Changes
+*******
+
+Deprecations
+************
+
+Bugs Fixed
+**********
+
+- **Config:** Added missing ``Config\Encryption::$cipher``.
+- **UserGuide:** Fixed the sample code for :ref:`encryption-compatible-with-ci3`.
+
+See the repo's
+`CHANGELOG.md <https://github.com/codeigniter4/CodeIgniter4/blob/develop/CHANGELOG.md>`_
+for a complete list of bugs fixed.

user_guide_src/source/installation/upgrade_433.rst

@@ -0,0 +1,49 @@
+##############################
+Upgrading from 4.3.2 to 4.3.3
+##############################
+
+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
+**********************
+
+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
+------
+
+- app/Config/Encryption.php
+    - The missing property ``$cipher`` is added for CI3
+      Encryption compatibility. See :ref:`encryption-compatible-with-ci3`.
+
+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_433
     upgrade_432
     upgrade_431
     upgrade_430