[#210] Adjust naming conventions for c binding

[elBoberido]

Notes for Reviewer

This PR adjust the naming convention for handle and pointer aliases for the C bindings

• _ref_h becomes _h_ref
• _mut_ptr becomes _ptr_mut

This makes is easier to find all occurrences of e.g. foo_ptr, independent of the mutability.

Additionally, the _h_ref types are now just an alias to *const _h. This makes quite a few casts obsolet.

Pre-Review Checklist for the PR Author

1. [x] Add sensible notes for the reviewer
2. [x] PR title is short, expressive and meaningful
3. [x] Relevant issues are linked in the References section
4. [x] Every source code file has a copyright header with SPDX-License-Identifier: Apache-2.0 OR MIT
5. [x] Branch follows the naming format (iox2-123-introduce-posix-ipc-example)
6. [x] Commits messages are according to this guideline
   • [x] Commit messages have the issue ID ([#123] Add posix ipc example)
   • [x] Commit author matches Eclipse Contributor Agreement (and ECA is signed)
7. [x] Tests follow the best practice for testing
8. [x] Changelog updated in the unreleased section including API breaking changes
9. [x] Assign PR to reviewer
10. [x] All checks have passed (except task-list-completed)

Checklist for the PR Reviewer

• [x] Commits are properly organized and messages are according to the guideline
• [x] Unit tests have been written for new behavior
• [x] Public API is documented
• [x] PR title describes the changes

Post-review Checklist for the PR Author

1. [x] All open points are addressed and tracked via issues

References

Relates to #210

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 78.96%. Comparing base (59b0d3d) to head (8bba75c). Report is 7 commits behind head on main.

Additional details and impacted files

[](https://app.codecov.io/gh/eclipse-iceoryx/iceoryx2/pull/406?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=eclipse-iceoryx) ```diff @@ Coverage Diff @@ ## main #406 +/- ## ========================================== + Coverage 78.93% 78.96% +0.02% ========================================== Files 194 194 Lines 22730 22730 ========================================== + Hits 17943 17948 +5 + Misses 4787 4782 -5 ``` [see 2 files with indirect coverage changes](https://app.codecov.io/gh/eclipse-iceoryx/iceoryx2/pull/406/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=eclipse-iceoryx)