Feature Request: Simplified import from a single ZIP (SQL + wp-content)

## What

Right now, importing an existing WordPress site into Studio requires a full site structure (core files, wp-config.php, etc.).

I'd like to propose a simplified import flow, similar to what Local (by WP Engine) does: import a single ZIP file that contains just two things:

- A `.sql` file (database dump)
- The `wp-content` folder

Studio would handle everything else automatically from there: scaffold WordPress core, generate a fresh local `wp-config.php`, detect and rewrite the database table prefix from the SQL dump, import the database, and drop in `wp-content` as-is.

## Why

Importing `wp-config.php` straight from production doesn't really make sense in a local dev context — you end up having to rewrite DB credentials, salts, `WP_HOME`/`WP_SITEURL`, debug constants, etc. right after import anyway. Same goes for pulling in full WordPress core files that Studio already provisions itself.

The only things actually needed to reproduce a site locally are the database and wp-content (themes, plugins, uploads). Local already does exactly this: you drop in a ZIP with the SQL dump + wp-content, it auto-detects the table prefix, and spins up a fully working local site in one step. It's a much faster and more reliable workflow, especially for agencies that just need a working local copy of a client's production/staging site from a DB export + wp-content, without reconstructing the whole environment by hand.

## Suggested solution

- Add an "Import from ZIP" option that accepts a single ZIP containing:
- One `.sql` file
- The `wp-content` folder
- Studio detects the table prefix automatically from the SQL dump (like Local does)
- Studio scaffolds WordPress core + generates its own local `wp-config.php` pointing to the new local DB with the detected prefix
- The SQL dump is imported into the new local database
- `wp-content` from the ZIP is used as-is

## Additional context

This would lower the friction for agencies working with client sites where we only have a DB export + wp-content, and specifically don't want (or need) to bring production `wp-config.php` or core files into the local environment.

The issue does not name specific files, tests, or entry points. Start by tracing Studio's existing site import flow and its database and wp-content handling, then determine how a ZIP containing one SQL file and wp-content can be validated and processed. Done means a local WordPress site is scaffolded with generated configuration, the detected table prefix, imported SQL, and the supplied wp-content.

Written by the indexing model from the issue text.