Add release entry for 1.4.0 (#12237)

* Add release entry for 1.4.0

* Mark version as 1.4.0

CHANGELOG.md

@@ -5,7 +5,7 @@ All major notable changes to this project will be documented in this file (start
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## Unreleased - YYYY-MM-DD
+## 1.4.0 - 2026-06-24
 
 ### Breaking Changes
 

src/backend/InvenTree/InvenTree/version.py

@@ -15,7 +15,7 @@ from datetime import timedelta as td
 from .api_version import INVENTREE_API_TEXT, INVENTREE_API_VERSION
 
 # InvenTree software version
-INVENTREE_SW_VERSION = '1.4.0 dev'
+INVENTREE_SW_VERSION = '1.4.0'
 
 # Minimum supported Python version
 MIN_PYTHON_VERSION = (3, 11)