separate support of rust 1.75 to avoid build issues

[milyin]

Description

The zenoh library have minimal supporting rust version 1.75 and should also work with the most recent Rust version.
The problem is that cargo's version resolution don't take packages MSRV into account. The rule is "Cargo uses the convention that only changes in the left-most non-zero component are considered incompatible" https://doc.rust-lang.org/cargo/reference/semver.html. This means that if we depend on static_init 1.0.3, the dependency resolves to latest one 1.0.4. This causes build failure wiht rust 1.75 because for static_init 1.0.4 MSRV=1.82

To support build with rust 1.75 the crate zenoh-pinned-deps-1-75 was added. It locks crates to last 1.75 compatible verisions, e.g "=1.0.3" for static_init.

Since rust 1.93 this is became harder to support. The static_init 1.0.3 can't be compiled with rust 1.93. This means that the zenoh-pinned-deps-1-75 should be used for 1.75 build only.

What does this PR do?

• removes zenoh-pinned-deps-1-75 from workspace to avoid it's influence to version selection
• adds test for build with latest rust

Why is this change needed?

• since rust 1.93 zenoh workspace build fails because of locks for 1.75

Related Issues

Description of zenoh-pinned-deps-1-75 #2082

Related PRs and repositories

• zenoh-c support of latest rust without losing rust 1.75 support zenoh-c#1201
• zenoh-cpp not related, no rust code
• zenoh-pico not related, no rust code
• zenoh-python remove rust 1.75 support zenoh-python#686
• zenoh-ts switched to rust 1.93 zenoh-ts#412
• zenoh-java move to rust 1.93 zenoh-java#425
• zenoh-kotlin switch to rust 1.93 zenoh-kotlin#612
• zenoh-csharp https://github.com/ZettaScaleLabs/zenoh-csharp/pull/33
• zenoh-go not related, no rust code

Plugins:

• zenoh-plugin-dds switch to rust 1.93 zenoh-plugin-dds#679
• zenoh-plugin-mqtt swhich to rust 1.93 zenoh-plugin-mqtt#593
• zenoh-plugin-webserver swithc to rust 1.93 zenoh-plugin-webserver#496
• zenoh-plugin-ros2dds swithc to rust 1.93 zenoh-plugin-ros2dds#646
• zenoh-plugin-ros1 switched to rust 1.93 zenoh-plugin-ros1#236 - decided not to do anything right now

Backends (plugins for storage manager plugin in the main zenoh repo):

• zenoh-backend-filesystem swithc to rust 1.93 zenoh-backend-filesystem#520
• zenoh-backend-influxdb switch to rust 1.93 zenoh-backend-influxdb#569
• zenoh-backend-rocksdb switch to rust 1.93 zenoh-backend-rocksdb#535
• zenoh-backend-s3 switch to rust 1.93 zenoh-backend-s3#508

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Labels: enhancement

✨ Enhancement Requirements

Since this PR enhances existing functionality:

• Enhancement scope documented - Clear description of what is being improved
• Minimum necessary code - Implementation is as simple as possible, doesn't overcomplicate the system
• Backwards compatible - Existing code/APIs still work unchanged
• No new APIs added - Only improving existing functionality
• Tests updated - Existing tests pass, new test cases added if needed
• Performance improvement measured - If applicable, before/after metrics provided
• Documentation updated - Existing docs updated to reflect improvements
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[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 72.52%. Comparing base (ee17f85) to head (7f0548e).
⚠️ Report is 1 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
commons/zenoh-util/src/log.rs	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2392      +/-   ##
==========================================
- Coverage   72.60%   72.52%   -0.08%     
==========================================
  Files         390      390              
  Lines       63261    63267       +6     
==========================================
- Hits        45928    45885      -43     
- Misses      17333    17382      +49     

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[Copilot]

Pull request overview

This PR separates Rust 1.75 support into an isolated CI crate to avoid dependency version conflicts between Rust 1.75 and 1.93. The core issue is that static_init 1.0.3 works with Rust 1.75 but not 1.93, while version 1.0.4 works with 1.93 but not 1.75.

Changes:

• Isolates Rust 1.75 testing to a new excluded workspace crate (ci/zenoh-1-75) that uses pinned dependencies
• Updates the default Rust toolchain from 1.85.0 to 1.93.0
• Removes zenoh-pinned-deps-1-75 from workspace members to prevent it from influencing dependency resolution

Reviewed changes

Copilot reviewed 7 out of 8 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
rust-toolchain.toml	Updates default toolchain to Rust 1.93.0
commons/zenoh-util/src/log.rs	Disables thread IDs/names in test logging due to memory leak (has typo)
ci/zenoh-1-75/src/lib.rs	New empty library for Rust 1.75 CI testing
ci/zenoh-1-75/Cargo.toml	New crate manifest that depends on zenoh with pinned deps
ci/valgrind-check/Cargo.toml	Removes zenoh-pinned-deps-1-75 dependency
Cargo.toml	Removes zenoh-pinned-deps-1-75 from workspace, excludes ci/zenoh-1-75, unpins buddy_system_allocator
Cargo.lock	Updates dependencies to newer versions now that pins are removed
.github/workflows/ci.yml	Simplifies Rust 1.75 testing, removes workarounds for nightly builds

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[Copilot]

Pull request overview

Copilot reviewed 7 out of 8 changed files in this pull request and generated 1 comment.

---

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[diogomatsubara]

LGTM, I made one small non-blocking comment about the authorship of the newly added Cargo.toml files for zenoh-1-75

[diogomatsubara]

Who's this person? We probably should update this to add the generic zenoh team as the author or at least add yourself as the author to the list.

[milyin]

No idea, something from some @OlivierHecart 's old template maybe. Replaced to Olivier's name

[diogomatsubara]

I left #2390 open for now but it'll likely be superseded by the work done in this PR. Once all the PRs land, we can close 2390 and let the automation do its thing.