Implement unified context function setup

The previous method of individually setting each context function in various files has been replaced with a unified function, SetUPContextFunctions, to streamline and centralize the process. This modification has been applied across multiple files including 'context.go', 'feature.go', 'filter.go', etc. This change enhances maintainability and code readability.

Signed-off-by: Christian Roessner c@roessner.co