feat(server): lightweight s3 client (#14348)

#### PR Dependency Tree


* **PR #14348** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added a dedicated S3-compatible client package and expanded
S3-compatible storage config (endpoint, region, forcePathStyle,
requestTimeoutMs, minPartSize, presign options, sessionToken).
* Document sync now broadcasts batched/compressed doc updates for more
efficient real-time syncing.

* **Tests**
* New unit and benchmark tests for base64 utilities and S3 multipart
listing; updated storage-related tests to match new formats.

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settings.</sub>
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/frontend/admin/src/modules/settings/config.ts

@@ -112,7 +112,7 @@ export const KNOWN_CONFIG_GROUPS = [
         key: 'blob.storage',
         sub: 'config',
         type: 'JSON',
-        desc: 'The config passed directly to the storage provider(e.g. aws-sdk)',
+        desc: 'The S3 compatible config for the storage provider (endpoint/region/credentials).',
       },
       {
         key: 'avatar.storage',
@@ -131,7 +131,7 @@ export const KNOWN_CONFIG_GROUPS = [
         key: 'avatar.storage',
         sub: 'config',
         type: 'JSON',
-        desc: 'The config passed directly to the storage provider(e.g. aws-sdk)',
+        desc: 'The S3 compatible config for the storage provider (endpoint/region/credentials).',
       },
       {
         key: 'avatar.publicPath',
@@ -175,7 +175,7 @@ export const KNOWN_CONFIG_GROUPS = [
         key: 'storage',
         sub: 'config',
         type: 'JSON',
-        desc: 'The config passed directly to the storage provider(e.g. aws-sdk)',
+        desc: 'The S3 compatible config for the storage provider (endpoint/region/credentials).',
       },
     ],
   } as ConfigGroup<'copilot'>,