Bump base image to 2026.02.0 with Python 3.14.3, use 3.14.3 in CI

This also bumps libcec used in the base image to 7.1.1, full changelog:
* https://github.com/home-assistant/docker/releases/tag/2026.02.0

Python changelog:
* https://docs.python.org/release/3.14.3/whatsnew/changelog.html

.github/workflows/builder.yml

@@ -14,7 +14,7 @@ env:
   UV_HTTP_TIMEOUT: 60
   UV_SYSTEM_PYTHON: "true"
   # Base image version from https://github.com/home-assistant/docker
-  BASE_IMAGE_VERSION: "2026.01.0"
+  BASE_IMAGE_VERSION: "2026.02.0"
   ARCHITECTURES: '["amd64", "aarch64"]'
 
 permissions: {}

.python-version

@@ -1 +1 @@
-3.14.2
+3.14.3