Add event subcommand (rc event add/list/remove) for bucket notification configuration

[simon-escapecode]

Summary

rc has no command for managing bucket event notification subscriptions. There is no way to configure which buckets send notifications to which targets using the CLI.

Motivation

Bucket event notification rules are stored as per-bucket metadata and must be set via the S3 PutBucketNotificationConfiguration API. There is no config file or environment variable alternative. Without a CLI command, users must call the S3 API directly to manage notification rules.

Proposed solution

Add an event subcommand with three actions:

rc event add   <alias/bucket> <arn> [--event <filter>]
rc event list  <alias/bucket>
rc event remove <alias/bucket> <arn>

This maps directly to GetBucketNotificationConfiguration and PutBucketNotificationConfiguration in the AWS S3 SDK, which is already a dependency.

A PR with a working implementation is forthcoming.

[overtrue]

Implemented in PR #55: #55

This adds:

• rc event add <alias/bucket> <arn> [--event <event>]
• rc event list <alias/bucket>
• rc event remove <alias/bucket> <arn>

I also added RustFS compatibility handling for PutBucketNotificationConfiguration responses that apply successfully but may return an SDK service error envelope.

[overtrue]

Implemented in PR #56: adds with core + S3 support and tests.\n\nPlease review: #56

[overtrue]

Correction: PR #56 adds event add/list/remove subcommands and underlying support.\nReview link: #56

[simon-escapecode]

Confirmed end-to-end: rc event add/list/remove working against patched RustFS server with MQTT notifications (rustfs/rustfs#2112). Happy for PR #56 to close this.

[overtrue]

Update: PR #56 was closed as duplicate. Please continue tracking this issue in existing PR #55.