fix(logs): handle partial success responses

[LouisDeconinck]

Fixes #2355

The OTLP logs exporter now decodes successful export responses and reports rejected log records from partial_success through the existing OpenTelemetry error handler. Successful partial exports still return SUCCESS.

Added focused WebMock coverage for the response and log message.

Validation:

• git diff --check passed
• Ruby/Bundler tests and RuboCop could not run because Ruby is not installed in the environment.

Signed-off-by: Louis Deconinck louis.dck@gmail.com
Assisted-by: Codex

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: LouisDeconinck / name: Louis Deconinck (9abf0cb)

[LouisDeconinck]

I've completed the EasyCLA authorization. Thanks — happy to address any review feedback.

[LouisDeconinck]

I've completed the EasyCLA authorization. Thanks — happy to address any review feedback.

[xuan-cao-swi]

LGTM, just wondering if you can update otlp trace exporter and otlp metrics exporter as well.
It will expand the scope of this PR, but it's ok if you want to minimize the scope for just logs exporter (we can just open another issue for other exporter).

[LouisDeconinck]

Thanks! I'd prefer to keep this PR scoped to the logs exporter — happy to open a follow-up issue for the otlp trace and metrics exporters so the same handling lands there too.