Use GID filtering to prevent loops (backport #834)

[mergify]

🦟 Bug fix

Fixes #788.

Summary

As mentioned in the issue, ignore_local_publications is hardcoded to true in factory.hpp. This DDS option
filters by DDS participant, not by node. In composition, all nodes share the same DDS participant, so messages from all sibling nodes are dropped.

The proposed fix is to replace ignore_local_publications with publisher GID-based filtering. At subscription creation time, the bridge collects its own publisher GIDs on the topic. In the callback, it compares each incoming message's publisher GID against that list and skips matches. This prevents loops in bidirectional bridges while allowing messages from other composed nodes.

I think the Gz transport side (SetIgnoreLocalMessages(true)) is OK because it works at the gz::transport::Node level, not the process level, so it should work correctly.

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers
• Was GenAI used to generate this PR? If so, make sure to add "Generated-by" to your commits. (See this policy for more info.)

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by and Generated-by messages.

---

This is an automatic backport of pull request #834 done by Mergify.