[#1144] zero copy send unions

[elfenpiff]

Notes for Reviewer

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  • Commit messages have the issue ID ([#123] Add posix ipc example)
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• Changelog updated in the unreleased section including API breaking changes
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Post-review Checklist for the PR Author

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References

Closes #1144

[Copilot]

Pull Request Overview

This PR adds support for deriving ZeroCopySend on union types. Previously, the derive macro only supported structs and enums, and would generate a compile error for unions. Now unions are handled by generating compile-time checks that ensure all fields implement ZeroCopySend.

Key changes:

• Modified the ZeroCopySend derive macro to handle Data::Union types
• Added field-by-field validation for union types similar to struct handling

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
iceoryx2-bb/derive-macros/src/lib.rs	Replaces the default case that returned a compile error with explicit union handling that validates all fields implement ZeroCopySend
doc/release-notes/iceoryx2-unreleased.md	Documents the new union support feature

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[codecov]

Codecov Report

❌ Patch coverage is 61.90476% with 16 lines in your changes missing coverage. Please review.
✅ Project coverage is 77.89%. Comparing base (2a452c2) to head (65d4d5d).
⚠️ Report is 62 commits behind head on main.

Files with missing lines	Patch %	Lines
iceoryx2-bb/derive-macros/src/lib.rs	0.00%	16 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1145      +/-   ##
==========================================
- Coverage   77.90%   77.89%   -0.01%     
==========================================
  Files         360      360              
  Lines       38788    38807      +19     
  Branches      807      807              
==========================================
+ Hits        30216    30230      +14     
- Misses       7933     7938       +5     
  Partials      639      639              

Flag	Coverage Δ
CPP	65.91% <ø> (ø)
Rust	77.85% <61.90%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
iceoryx2-bb/elementary/src/bump_allocator.rs	100.00% <100.00%> (ø)
iceoryx2-bb/memory/src/bump_allocator.rs	80.30% <100.00%> (ø)
iceoryx2-bb/memory/src/one_chunk_allocator.rs	84.40% <100.00%> (+0.14%)	⬆️
iceoryx2-bb/memory/src/pool_allocator.rs	94.87% <100.00%> (ø)
iceoryx2-bb/posix/src/memory.rs	89.81% <100.00%> (+0.09%)	⬆️
iceoryx2/src/active_request.rs	92.17% <100.00%> (ø)
iceoryx2/src/pending_response.rs	89.08% <100.00%> (ø)
iceoryx2/src/port/client.rs	92.85% <100.00%> (ø)
iceoryx2/src/port/publisher.rs	93.37% <100.00%> (ø)
iceoryx2/src/port/server.rs	93.56% <100.00%> (ø)
... and 2 more

... and 107 files with indirect coverage changes

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