docs: Rebrand OptimizR to Optimiz-rs throughout documentation

Updated Branding in ReadTheDocs:
- ✅ All 'OptimizR' → 'Optimiz-rs' (17 files)
- ✅ Project name in conf.py
- ✅ HTML title and short title
- ✅ All algorithm documentation
- ✅ Getting started guide
- ✅ Installation guide
- ✅ Theory/mathematical foundations
- ✅ Archive documentation

Documentation now consistently uses the new 'optimiz-rs' branding that
matches both PyPI and crates.io package names.

Note: Python module name 'optimizr' in import statements intentionally
unchanged (that's the actual module name).

docs/source/algorithms/differential_evolution.md

@@ -303,7 +303,7 @@ print(f"Function evaluations: {result.nfev}")
 
 ## Adaptive Control (jDE)
 
-OptimizR implements **jDE** (self-adaptive DE), where the parameters $F$ and $CR$ 
+Optimiz-rs implements **jDE** (self-adaptive DE), where the parameters $F$ and $CR$ 
 evolve with the population:
 
 $$