RSCBC-264: OrphanReporter - Replace log sink and increase log level

[Matt-Woz]

Changes

• Move orphan reporting log level up from debug to warn
• Remove log sink and replace it in tests with a fmt subscriber writer

[Copilot]

Pull request overview

This PR updates orphan reporting to emit via tracing at info level instead of using a configurable log sink, and adjusts tests to capture output through a tracing-subscriber fmt writer.

Changes:

• Switch orphan reporter summary logging from debug! to info! and remove the custom log_sink plumbing.
• Remove log_sink from OrphanReporterConfig (and related types/helpers).
• Update orphan reporter tests to capture logs using a custom MakeWriter + tracing-subscriber.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
sdk/couchbase-core/src/orphan_reporter.rs	Removes sink-based logging and emits orphan summaries via tracing::info!.
sdk/couchbase-core/src/options/orphan_reporter.rs	Drops log_sink from the public config API.
sdk/couchbase-core/tests/orphan_reporter_test.rs	Replaces sink-based assertions with tracing-subscriber output capture.
sdk/couchbase-core/Cargo.toml	Adds tracing-subscriber as a dev-dependency for the updated tests.

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[github-actions]

Bencher Report

Branch	RSCBC-264-22866494815-137-1
Testbed	ubuntu-latest

Click to view all benchmark results

Benchmark	Latency	Benchmark Result microseconds (µs) (Result Δ%)	Upper Boundary microseconds (µs) (Limit %)
query	📈 view plot 🚷 view threshold	427.03 µs (+1.85%) Baseline: 419.29 µs	482.18 µs (88.56%)
upsert_and_get	📈 view plot 🚷 view threshold	406.66 µs (+1.99%) Baseline: 398.74 µs	458.56 µs (88.68%)

🐰 View full continuous benchmarking report in Bencher

[github-actions]

Bencher Report

Branch	RSCBC-264-22867023419-140-1
Testbed	ubuntu-latest

Click to view all benchmark results

Benchmark	Latency	Benchmark Result microseconds (µs) (Result Δ%)	Upper Boundary microseconds (µs) (Limit %)
query	📈 view plot 🚷 view threshold	446.46 µs (+6.48%) Baseline: 419.29 µs	482.18 µs (92.59%)
upsert_and_get	📈 view plot 🚷 view threshold	413.83 µs (+3.78%) Baseline: 398.74 µs	458.56 µs (90.25%)

🐰 View full continuous benchmarking report in Bencher