Move aws-sdk to devDependencies (type-only usage)

[drernie]

Sub-task of #4869.

Finding

Every `aws-sdk` import in `catalog/app/` is type-only (`import type { S3 } from 'aws-sdk'` etc.). Type-only imports are erased at compile time, so `aws-sdk` v2 is not in the runtime bundle.

Verified: `grep -rE "from ['\"]aws-sdk['\"]" catalog/app/ | grep -v "import type"` → no matches.

This means the audit's recommendation to migrate to AWS SDK v3 is over-scoped. The dependency exists only to provide TypeScript types.

Scope

Two reasonable options:

1. Move `aws-sdk` from `dependencies` → `devDependencies`. Smallest change. Still triggers Dependabot CVE PRs (it scans devDeps), but the framing is correct and reviewers can fast-merge knowing it's never executed.
2. Replace `aws-sdk` v2 types with `@aws-sdk/client-*` v3 types (S3, Athena, Bedrock — the three clients used). Eliminates the CVE-prone v2 type package entirely. Modest refactor of import paths in ~18 files.

Recommend option 1 first (15 min) and revisit option 2 only if v2 keeps generating PR noise.

Files affected (option 1)

Just `catalog/package.json` + lockfile.

Files affected (option 2, for reference)

```
app/utils/CatalogSettings.tsx
app/utils/BucketPreferences/Provider.tsx
app/components/Assistant/Model/Bedrock.ts
app/components/Assistant/Model/ContextFiles.tsx
app/components/Assistant/Model/GlobalContext/preview.ts
app/components/FileEditor/loader.ts
app/components/Preview/loaders/useGate.ts
app/components/Preview/loaders/useGate.spec.ts
app/containers/Bucket/Summarize.tsx
app/containers/Bucket/PackageDialog/Uploads.tsx
app/containers/Bucket/PackageDialog/Inputs/Files/S3FilePicker.tsx
app/containers/Bucket/Queries/Athena/model/requests.ts
app/containers/Bucket/requests/bucketListing.ts
app/containers/Bucket/requests/object.ts
app/containers/Bucket/requests/package.ts
app/containers/Bucket/requests/object.spec.ts
app/containers/Bucket/Overview/Overview.tsx
app/containers/Bucket/Overview/Header.tsx
```