chore: Update changelog for #85 (#87)

* CompatHelper: bump compat for Optim to 2, (keep existing compat)

* chore: Add NLSolversBase as direct dependency

* fix: Don't assume only_fg! imported by Optim

* chore: Increment patch number

* chore: Update CHANGELOG for version 0.4.5

---------

Co-authored-by: CompatHelper Julia <compathelper_noreply@julialang.org>

Author: sethaxen

CHANGELOG.md

@@ -12,6 +12,12 @@
 
 ### Documentation
 
+## v0.4.5 (2026-02-03)
+
+### Maintenance
+
+- Support Optim v2 ([#85](https://github.com/arviz-devs/PosteriorStats.jl/pull/85))
+
 ## v0.4.4 (2026-01-19)
 
 ### Documentation