**I want to create a single page app based to use the PDP Backfill system. User typically use
`aws s3` commands or the AWS console to upload CSV and JSON files to a special S3 bucket
that triggers the backfill.

Learn more about the backfill at @_tmp/How-to-backfill-identities-to-PP-1f497177520f803585eac35e11517ccd.md.

## Requirements

User Interaction

- The user will select CSV files from their local machine.
- The user will select a JSON file from their local machine.
- Define the folder path within the S3 bucket where the files will be uploaded
- The user will review the selected files.
- The user will click "Submit Backfill" or "Cancel"

Application actions:

- The application will upload the CSV files to S3 using AWS SDKs.
- The application will upload the JSON manifest file to S3 using AWS SDKs.
- The application will return a success or failure message to the user after the upload.

## Tech Stack

Create a basic single page app the `src/` directory with the following tech stack.

- Framework: React 18 with TypeScript
- Router: React Router v5
- UI Library: @theorchard/suite-frontend (internal Suite components)
- Build Tool: Webpack (configured via Suite frontend)
- Validation: Zod schemas for runtime type safety
- Linting/Formatting: Biome

Use /Users/tcalhoun/work/collab/ratoui/claude-dashboard/frontend as inspiration for this application. It uses
internal UI components. See the package.json:

```text
        "@theorchard/suite-components": "12.30.1",
        "@theorchard/suite-frontend": "8.10.1",
        "@theorchard/suite-icons": "7.15.0",
```**