Add “Export as JSON” button in Database → Collection → Documents view

### 🔖 Enhancement description

Add an option in the Database Console UI to export collection documents as a JSON file.

Currently, users can view and filter documents in a collection, but there is no direct way to export the documents from the Console. This enhancement would add an “Export as JSON” button in the Documents view that allows users to download the currently filtered documents as a .json file.

The export should respect active search queries and filters applied in the UI.

### 🎤 Pitch

In many development workflows, developers need to:

- Back up collection data

- Migrate data between environments

- Debug data locally

- Share sample datasets

Currently, this requires writing custom scripts using the SDK or API. Adding a built-in “Export as JSON” option in the Console would significantly improve developer experience.

Proposed behavior:

- Add an “Export JSON” button in Database → Collection → Documents toolbar

- Use the existing listDocuments API

- Respect active filters/search queries

- Handle pagination to fetch all matching documents

- Trigger download using the browser’s Blob API

- Name the file based on the collection (e.g., users.json)

This would be a Console-only UI enhancement and would not require backend changes.

I’d be happy to work on this feature if it aligns with the project direction.

### 👀 Have you spent some time to check if this issue has been raised before?

- [x] I checked and didn't find similar issue

### 🏢 Have you read the Code of Conduct?

- [x] I have read the [Code of Conduct](https://github.com/appwrite/.github/blob/main/CODE_OF_CONDUCT.md)