feat(storage): enable App-Centric Observability (ACO) support in Otel

[nidhiii-27]

Adding support for App-Centric Observability (ACO) by ensuring GCS spans include the required id and location resource attributes: gcp.resource.destination.id and gcp.resource.destination.location

• Implemented AcoSpanBuilder and AcoSpan to intercept setAttribute("gsutil.uri", ...), startSpan and endSpan calls
• Added a package-private BucketMetadataCache using a bounded LinkedHashMap (10,000 entries) to manage bucket-to-location mappings with low memory overhead
• Triggered asynchronous GetBucket metadata resolution on cache misses using a dedicated ThreadPoolExecutor
• Managing cache eviction or fallback attributes in case of 404/403

Validated via OtelStorageDecoratorAcoUnitTest and integration tests (ITOpenTelemetryTest, ITOpenTelemetryMPUTest)

[gemini-code-assist]

Code Review

This pull request introduces a bucket metadata caching mechanism to enrich OpenTelemetry spans with destination resource IDs and locations. It adds AcoSpan and AcoSpanBuilder for span lifecycle management, a BucketMetadataCache for storage, and background fetching logic in OtelStorageDecorator. Reviewer feedback includes using constants for attribute keys, optimizing GCS API calls by selecting specific fields, and reducing the executor shutdown timeout to improve closing efficiency.