feat: user-events logs exporter - add support for Resource attributes

[cijothomas]

Adding opt-in support for Resource attributes.

[codecov]

Codecov Report

Attention: Patch coverage is 20.96774% with 49 lines in your changes missing coverage. Please review.

Project coverage is 48.1%. Comparing base (a06d318) to head (6c895a7).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
...pentelemetry-user-events-logs/src/logs/exporter.rs	20.5%	27 Missing ⚠️
opentelemetry-user-events-logs/src/lib.rs	0.0%	16 Missing ⚠️
...entelemetry-user-events-logs/src/logs/processor.rs	50.0%	6 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main    #288     +/-   ##
=======================================
- Coverage   48.3%   48.1%   -0.2%     
=======================================
  Files         69      69             
  Lines       9479    9529     +50     
=======================================
+ Hits        4581    4589      +8     
- Misses      4898    4940     +42     

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[Copilot]

Pull Request Overview

Adds optional Resource attribute forwarding to the user-events log exporter, allowing selected Resource keys to be emitted alongside each log.

• Extends ProcessorBuilder with a with_resource_attributes option and passes chosen keys to the exporter
• Updates UserEventsExporter to store, convert, and include those Resource attributes in PartC of the event payload
• Adjusts tests and changelog to cover the new feature

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/logs/processor.rs	Added resource_attributes field, with_resource_attributes builder, and new constructor parameter
src/logs/exporter.rs	Extended exporter state, set_resource logic, PartC emission, and conversion helper
src/lib.rs	Updated test setup to configure and assert on resource attributes
CHANGELOG.md	Documented the new with_resource_attributes method

Comments suppressed due to low confidence (1)

opentelemetry-user-events-logs/src/logs/exporter.rs:22

• The code refers to Key and AnyValue on this line but neither is imported. Add use opentelemetry::Key; and import AnyValue from the crate where it's defined (e.g. use eventheader::AnyValue;) so the code compiles.

    attributes_from_resource: Vec<(Key, AnyValue)>,