[21128] Make all public headers .hpp

[JesusPoderoso]

Description

This PR performs the following changes in the public API:

• Updates header guard following this structure: FOLDER_SUBFOLDER__FILENAME_HPP
• Updates the doxygen file reference /* @file filename.hpp
• Updates the file name filename.h -> filename.hpp
• Updates the usages (includes) of the filename
• One commit per header changed

This PR should be merged before (and it is on top of) the following PRs (in order):

• [21129] Migrate fastrtps namespace to fastdds #4898
• [21159] Remove include/fastrtps #4930

This PR also needs an update in Fast DDS Python, Shapes Demo, Discovery Server and Fast DDS Gen, and regenerate all types:

• [21128] Update guards and extenstion .h to .hpp in headers Fast-DDS-Gen#358
• [21128] Adjust for Fast DDS public headers migration to .hpp  Fast-DDS-docs#825
• [21128] Adjust for Fast DDS public headers migration to .hpp Fast-DDS-python#148
• [21128] Adjust for Fast DDS public headers migration to .hpp ShapesDemo#148
• [21128] Adjust for Fast DDS public headers migration to .hpp Discovery-Server#89

Contributor Checklist

• Commit messages follow the project guidelines.
• The code follows the style guidelines of this project.
• N/A Tests that thoroughly check the new feature have been added/Regression tests checking the bug and its fix have been added; the added tests pass locally
• N/A Any new/modified methods have been properly documented using Doxygen.
• N/A Any new configuration API has an equivalent XML API (with the corresponding XSD extension)
• ❌ Changes are backport compatible: they do NOT break ABI nor change library core behavior.
• ❌ Changes are API compatible.
• New feature has been added to the versions.md file (if applicable).
• N/A New feature has been documented/Current behavior is correctly described in the documentation.
• N/A Applicable backports have been included in the description.

Reviewer Checklist

• The PR has a milestone assigned.
• The title and description correctly express the PR's purpose.
• Check contributor checklist is correct.
• Check CI results: changes do not issue any warning.
• Check CI results: failing tests are unrelated with the changes.