[CDF-25921] 🗄 Create data plugin (#2102)

# Description

This PR adds the alpha flag `v07` which we will use to put all `v07`
features behind. This will make it easy to make the minor PR when the
time comes.

It also introduce a `data` app and puts `download/upload/purge` behind
it. I removed download and upload from the entry app as they are both
alpha, but purge cannot be removed until the actual release is done.

<img width="700" height="294" alt="image"
src="https://github.com/user-attachments/assets/d9a8ac2b-9455-45a4-88ca-ef6bec384741"
/>


## Changelog

- [x] Patch
- [ ] Skip

## cdf

### Added

- [alpha] Created new plugin `cdf data` that will hold `cdf data
download/upload/purge`.

### Removed

- [alpha] The `cdf download/upload` commands have been moved to `cdf
data download/upload`.

## templates

No changes.
