Add Add per-channel constraints parameters to OptimizationGrid.optimize(...)`.

PiperOrigin-RevId: 740470489

Author: viktoriias

CHANGELOG.md

@@ -29,6 +29,8 @@ To release a new version (e.g. from `1.0.0` -> `2.0.0`):
 * Refactor args in `create_optimization_grid` to be consistent with
   `optimize(...)`.
 * Fix response curves for KPI-based optimization.
+* Add Add per-channel constraints parameters to
+ `OptimizationGrid.optimize(...)`.
 
 ## [1.0.7] - 2025-03-19