feat(framework): Update changelog for v1.26.1 (#6539)

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Javier <jafermarq@users.noreply.github.com>

Author: 3 people

framework/docs/source/ref-changelog.md

@@ -1,6 +1,22 @@
 # Changelog
 
-## Unreleased
+## v1.26.1 (2026-02-07)
+
+### Thanks to our contributors
+
+We would like to give our special thanks to all the contributors who made the new version of Flower possible (in `git shortlog` order):
+
+`Charles Beauville`, `Chong Shen Ng`, `Copilot`, `Daniel J. Beutel`, `Heng Pan`, `Javier`, `Taner Topal` <!---TOKEN_v1.26.1-->
+
+### What's new?
+
+- **Fix client resource handling in local simulations** ([#6536](https://github.com/adap/flower/pull/6536))
+
+  Fix an issue in local simulations where backend configuration is not correctly propagated, causing virtual client resource settings such as CPU and GPU allocations in the Flower Configuration to be ignored.
+
+- **Update framework documentation** ([#6528](https://github.com/adap/flower/pull/6528), [#6530](https://github.com/adap/flower/pull/6530))
+
+- **General improvements** ([#6526](https://github.com/adap/flower/pull/6526), [#6493](https://github.com/adap/flower/pull/6493), [#6534](https://github.com/adap/flower/pull/6534), [#6531](https://github.com/adap/flower/pull/6531), [#6523](https://github.com/adap/flower/pull/6523), [#6529](https://github.com/adap/flower/pull/6529), [#6501](https://github.com/adap/flower/pull/6501))
 
 ## v1.26.0 (2026-02-05)