refactor(rust): let callers name the meter provider type

[yordis]

• The meter constructor was the only generated Rust constructor that hid its provider type, so callers could not name it explicitly the way they can for the logger and tracer.
• A named type parameter keeps the generated public API consistent and leaves room to evolve without breaking callers.

[cursor]

PR Summary

Low Risk
Template and golden-test output only; same runtime logic with a signature tweak that should remain source-compatible for typical &provider call sites.

Overview
Updates generated Rust Meter::new so the meter provider is a named generic P instead of an impl MeterProvider reference parameter.

The Jinja template meter.rs.j2 and all matching expected meter.rs fixtures under templates/code/rust/tests/*/expected/ are kept in sync with the new signature new<P: opentelemetry::metrics::MeterProvider + ?Sized>(provider: &P, ...). Behavior inside new is unchanged; only the public type signature changes so call sites can pin or infer a concrete provider type (e.g. when passing wrapped providers).

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[coderabbitai]

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• Run ID: 745d709d-f005-4ced-9243-0db2bde481be

📥 Commits

Reviewing files that changed from the base of the PR and between 039cf30 and 464e743.

📒 Files selected for processing: 10

• templates/code/rust/meter.rs.j2
• templates/code/rust/tests/allocations/expected/meter.rs
• templates/code/rust/tests/histogram_boundaries_by_unit/expected/meter.rs
• templates/code/rust/tests/histogram_boundaries_by_unit_params/expected/meter.rs
• templates/code/rust/tests/imported/expected/meter.rs
• templates/code/rust/tests/imported_typed/expected/meter.rs
• templates/code/rust/tests/literal_escaping/expected/meter.rs
• templates/code/rust/tests/metrics/expected/meter.rs
• templates/code/rust/tests/naming/expected/meter.rs
• templates/code/rust/tests/params/expected/meter.rs

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Walkthrough

The Rust meter template and its expected outputs now declare the MeterProvider type as a named generic parameter. The trait bound, ?Sized constraint, and provider handling remain unchanged.

Changes

Rust Meter Signature

Layer / File(s)	Summary
Update the meter signature and expected outputs templates/code/rust/meter.rs.j2, templates/code/rust/tests/*/expected/meter.rs	Meter::new uses a named generic parameter P bounded by MeterProvider + ?Sized. The expected Rust outputs reflect the same signature. The remaining parameters and provider handling are unchanged.

Priority: ⬇️ Low

Estimated code review effort: 1 (Trivial) | ~3 minutes

Change: Refactor

Merge Risk: ⚪ Minimal · up to 464e7

The change is limited to naming an existing generic provider type and is ready to merge after normal checks.

Pre-merge checks: 4 · 1

Failed checks: 1 warning

Check name	Status	Explanation	Resolution
Docstring Coverage		Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 9 functions across 9 files. (1 skipped: 1 …	Write docstrings for the functions missing them to satisfy the coverage threshold.

Passed checks: 4 passed

Check name	Status	Explanation
Description check		The description clearly explains the Rust API change and its purpose. It matches the changeset.
Title check		The title accurately and concisely describes the main change: callers can name the meter provider type.
Linked Issues check		Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check		Check skipped because no linked issues were found for this pull request.

Full details: Docstring Coverage

Explanation

Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 9 functions across 9 files. (1 skipped: 1 unsupported.)

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_{A rabbit checked the meter's type,
And named its P with care;
The bound stayed put, the code stayed still,
The tests now match the template,
Then hopped away through syntax fair.}

_{Comment @coderabbitai help to get the list of available commands.}