docs: Enhance build-iapp section for clarity and refactor CLI reference

- Improved the guide in the build-iapp section to provide clearer instructions on processing protectedData and clarifying input-output relationships.
- Refactored the iApp generator CLI reference for better organization and usability.

Author: Le-Caignec

README.md

@@ -253,3 +253,5 @@ for input parameters:
 - Rework Advanced iApp building guides. (from "old" protocol doc)
 - Rework src\get-started\protocol\oracle.md (transfer to guide or rewrite)
 - Talk about iApp secret
+- Improve Guide in build-iapp section - be more clear for builder ( how to process process protectedData, clarify input-output guide)
+- refactor iapp generator cli reference